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61 Commits

Author SHA1 Message Date
Xingbo Wang
81369fc170 Fix async secondary catch-up on deleted SSTs (#15438)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15438

Fix a RocksDB secondary with `open_files_async = true` latching on `PathNotFound` during `TryCatchUpWithPrimary()`.

**Why:** With `open_files_async = true` and `max_open_files = -1`, a secondary's catch-up could fail with `PathNotFound` on a table that was live at open time (most reachably in a non-default column family) but which the primary compacted away before the background async opener pinned it. The error latched in the tailer's status, so the secondary never advanced again and had to be closed and reopened. With `open_files_async = false` the same sequence caught up fine. This blocks enabling async secondary open where it would otherwise cut cold-open time substantially.

**Previous behavior:** In `VersionEditHandlerPointInTime::MaybeCreateVersionBeforeApplyEdit`, a negative-edge `LoadTableHandlers()` failure skipped the unrecoverable point-in-time only when the status was `Corruption`; a `PathNotFound` was returned as-is and latched. During a secondary's catch-up, `open_files_async` leaves recovery-time tables unpinned until the background opener reaches them, so `LoadTableHandlers()` could try to open a file the primary had already deleted.

**New behavior:** That negative-edge failure path now also treats `PathNotFound` as a missing file (skip this point-in-time and continue) when `no_error_if_files_missing_` is set, mirroring the tolerance `VersionEditHandler::LoadTables()` already applies. Catch-up continues past the transient state and installs the current version, so the secondary advances instead of latching.

**Implementation:**
- `db/version_edit_handler.cc`: broaden the negative-edge skip condition in `VersionEditHandlerPointInTime::MaybeCreateVersionBeforeApplyEdit` from `s.IsCorruption()` to also include `s.IsPathNotFound() && no_error_if_files_missing_`.
- `db/db_secondary_test.cc`: add `DBSecondaryTest.OpenFilesAsyncNonDefaultCfCatchUp`, a regression test that opens an async secondary with a non-default column family, holds the background opener back so the open-time table stays unpinned, has the primary flush and `CompactRange(kForce)` to replace and delete that table, then asserts `TryCatchUpWithPrimary()` succeeds and reads the new value.

**Safety boundaries:** The change only affects point-in-time handlers that opted into missing-file tolerance (`no_error_if_files_missing_`, set by secondary/follower tailing and best-efforts recovery); it does not relax error handling for strict recovery. It does not change the `trust_manifest_recovery_` / `defer_sst_file_opening_` paths, which already skip opening.

**Validation and limitations:** The regression test covers async secondary catch-up after deletion of an open-time SST in a non-default column family. Validation covers async opening, catch-up, memtable retention, and repeated scheduling changes. Strict recovery, API and file formats are unchanged. The full supported platform matrix has not been run locally.

Reviewed By: jaykorean

Differential Revision: D125378257

fbshipit-source-id: 3dd23c2f763e4e744c9f38fb77dfdfb3f554ee7f
2026-10-21 17:51:53 -07:00
Xingbo Wang
baa4d373a6 Commit authoritative OPTIONS file numbers in MANIFEST (#15305)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15305

Why the change is required:

Column-family topology is durable in MANIFEST, while its operational
configuration snapshot is stored in a separate OPTIONS file.
CreateColumnFamily and DropColumnFamily previously committed MANIFEST first
and wrote OPTIONS afterward. An OPTIONS I/O failure could therefore make the
API report failure after the topology change was already durable.
Persisted-options readers also selected the highest file number and could
consume an orphan left by a failed publication.

Previous behavior:

RocksDB had no durable correspondence between a MANIFEST state and the
OPTIONS snapshot describing it. LoadLatestOptions and
GetLatestOptionsFileName treated the highest-numbered OPTIONS file as
authoritative. Column-family creation and deletion returned the later OPTIONS
persistence error even when their MANIFEST edit had already succeeded.
Multi-column-family operations wrote a complete OPTIONS snapshot after every
successful member, producing quadratic OPTIONS bytes.

Ordinary DB::Open consumes caller-supplied DB and column-family options rather
than loading OPTIONS. This change preserves that contract.

New behavior:

Add the default-disabled experimental DB option
track_options_file_number_in_manifest. Its value is serialized into each
OPTIONS file so the selection rule is self-describing and participates in the
normal DB-options compatibility checks.

When enabled, RocksDB first durably creates and renames OPTIONS-N and then
commits N with one safely ignorable MANIFEST field. A normal OPTIONS rotation
uses one MANIFEST commit. Column-family creation and deletion prewrite the
proposed snapshot and commit its number together with a topology edit in the
same VersionEdit. A failure before the OPTIONS file is durable changes no
topology. A failure after the file is durable but before MANIFEST commit leaves
an orphan that binding-aware readers ignore, while the previous committed
snapshot remains authoritative.

Each multi-CF create or drop writes one proposed snapshot, independent of the
batch size. Create commits the new number with the first successful add; drop
commits it with the last successful drop. Existing partial-success semantics
can therefore leave a committed snapshot with extra CFs, but never one missing
a live MANIFEST CF. Persisted-options APIs filter this safe superset against
recovered MANIFEST membership. A snapshot missing a live CF is corruption.
DB::Open with create_missing_column_families uses the same batched path.

If the newest OPTIONS file has tracking disabled, it retains the legacy
highest-numbered-file behavior, including after an old or disabled writer has
run. If it has tracking enabled, readers use the recovered MANIFEST commit and
reject newer tracked orphans. A missing usable commit falls back to the highest
tracked snapshot for RepairDB and legacy-rewrite recovery. DB open logs that
fallback through its configured logger; logger-less utility APIs remain
silent. Writable open removes rejected tracked orphans when local obsolete-file
deletion is enabled. Read-only open never mutates the DB directory.

A DB with no recovered commit and tracking disabled takes the legacy fast path
without parsing the newest OPTIONS file. When inspection is required, RocksDB
reads only the tracking marker. Marker-read failures used for selection do not
fail DB open; a recovered commit remains authoritative and ambiguous newer
candidates are conservatively retained.

The first topology change after enabling tracking first binds the current
topology, so failure of the proposed change cannot make its orphan
authoritative. MANIFEST failure during an ordinary tracked OPTIONS rotation
also enters the existing manifest-write background-error path.

Implementation:

- Add the safely ignorable CommittedOptionsFileNumber VersionEdit field and
  carry it through recovery, MANIFEST snapshots, rollover, and subset
  checkpoints.
- Persist the tracking marker through C++, C, and Java options, generated
  round-trip coverage, compatibility checking, and db_stress configuration.
- Centralize binding-aware selection for DB open and public persisted-options
  APIs. Reuse RecoveryContext's directory listing, use a narrow marker scan,
  and recover live CF names while replaying MANIFEST.
- Filter manifest-selected safe-superset snapshots to live MANIFEST CFs in
  LoadLatestOptions and compatibility verification without discarding their
  option maps.
- Prevalidate and sanitize CF batches outside the DB mutex, write one complete
  snapshot while options_mutex_ serializes topology changes, and hold the DB
  mutex only for the existing individual MANIFEST commits. Batch missing-CF
  creation during DB open follows the same locking boundary.
- Keep the committed snapshot live in cleanup and live-file APIs, and make
  subset checkpoints write an OPTIONS snapshot and filtered MANIFEST with
  identical membership in tracked and legacy modes.
- Preserve the first partial multi-CF drop error while consuming legacy
  OPTIONS persistence Status, and sync the checkpoint MANIFEST directory after
  replacement.
- Pass checkpoint helper callbacks by reference and group VersionEdit storage
  by alignment so the new paths add neither callback copies nor avoidable
  object padding.

Safety boundaries and unsupported cases:

- Tracking defaults to false. Disabled writers and never-tracked databases
  retain legacy write ordering and highest-numbered selection.
- Older binaries safely ignore the new MANIFEST tag and continue choosing the
  highest OPTIONS number. Downgrade is readable but not crash-atomic: an old
  binary can consume a tracked orphan. That is the same class of
  OPTIONS/MANIFEST inconsistency as the previous behavior.
- A rollback binary must know the serialized option name before the feature is
  enabled. Exact compatibility checks intentionally report a mismatch when the
  caller's tracking setting differs from the persisted snapshot.
- A newer untracked OPTIONS file deliberately supersedes an older committed
  number, allowing an old or disabled writer to become authoritative without
  rewriting MANIFEST.
- Reactive secondary and follower instances do not enforce or repair the
  binding. Ordinary DB::Open still uses caller-supplied options.
- Writable open does not delete rejected tracked or ambiguous files when a
  compaction service owns OPTIONS-file retention. Read-only open performs no
  repair writes.
- Direct consumers that scan OPTIONS filenames themselves are unchanged; the
  binding is enforced by RocksDB's persisted-options APIs.
- If the committed snapshot is missing and only tracked candidates remain,
  selection intentionally falls back to the highest candidate so RepairDB
  output remains usable.

Validation coverage and known limitations:

Focused coverage exercises encoding compatibility, tracked and legacy
selection, the never-tracked open fast path, marker-read failures, exact
tracking-marker compatibility, activation and disable/re-enable transitions,
batched create/drop and create-missing behavior, partial-batch safe supersets,
OPTIONS/MANIFEST failure injection, background-error propagation, orphan
cleanup and retention, read-only non-mutation, subset-checkpoint behavior,
stale OPTIONS recovery, RepairDB option sanitization, and transient
read-corruption reconstruction. The assertion-enabled full executable suite
passes. The repository check-format and check-sources wrappers cannot run
because they invoke Git inside this Sapling checkout; fbsource lint is used
instead. Cross-platform CI is not part of local validation.

Reviewed By: pdillinger

Differential Revision: D123104845

fbshipit-source-id: 77d94c989243c3f3f9fedfa81fa364c166250303
2026-10-11 10:39:30 -07:00
Xingbo Wang
19b6f85266 Support async file open for SecondaryDB (#15294)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15294

Why the change is required:
`open_files_async` reduces startup latency by moving SST validation and table-reader opening to background work, but `DB::OpenAsSecondary()` still performed that work synchronously.

Previous behavior:
A secondary using `open_files_async=true` replayed its MANIFEST through `ReactiveVersionSet`, synchronously verified and opened every current SST, and only then returned. The option therefore provided no startup benefit for secondary instances.

New behavior:
`DB::OpenAsSecondary()` can now return after installing its initial read view and start initial SST validation and table-reader pinning through the existing asynchronous opener. With `max_open_files=-1`, the opener processes all current SSTs in the background; a finite table cache can stop the eager pass at capacity and validate remaining files on demand. Later `TryCatchUpWithPrimary()` rounds remain synchronous. Async-open failures notify listeners and are latched according to the existing severity and `paranoid_checks` policy. If an error is not latched, a later read retries the file access and reports a persistent failure. A latched error requires fixing the underlying problem and reopening the secondary. Read-only instances do not start write-oriented recovery.

Implementation:
Initial reactive MANIFEST replay can defer SST verification and handler loading. The deferral is immutable constructor state on `ReactiveVersionSet`, is cleared before catch-up mode, and is restricted to normal secondary recovery. `VersionBuilder::GetAndClearIntermediateFiles()` now moves out and clears its own historical add-then-delete bookkeeping so callers cannot accidentally retain stale state. Secondary open schedules the background opener after publishing the read view. Its context pins the captured Versions and column families, including retained secondary handles whose column family was subsequently dropped by the primary. Existing table-reader opening performs SST size and unique-ID validation, avoiding a separate serial metadata pass. Closing the DB or canceling background work safely cancels a queued opener or waits for a running opener. Read-only async-open errors use an ErrorHandler path that notifies listeners without automatic recovery. Secondary async open explicitly rejects FIFO compaction.

Safety, compatibility, and limitations:
The default `open_files_async=false` path and existing primary async-open behavior are unchanged. WAL and blob recovery, as well as later secondary catch-up, remain synchronous. Follower DB and `OpenAndCompact()` do not use this deferral. There are no file-format, ABI, or public API signature changes. Secondary async open requires `skip_stats_update_on_db_open=true` and does not support FIFO compaction. Applications must keep files accessible by coordinating deletion with the primary or by using an Env/FileSystem that delays physical deletion until every instance releases a file. With asynchronous opening, `max_open_files=-1` cannot guarantee every SST is pinned before `OpenAsSecondary()` returns; the table-files-only `max_open_files=-1` workaround applies only when asynchronous opening is disabled. No completion API is added.

Validation covers initial deferral and pinning, synchronous catch-up, table-reader detection of physical-size mismatch, FIFO rejection, listener-adjusted errors and synchronous read retry, retained handles after primary column-family deletion, close and explicit cancellation with no HIGH-priority worker, stopping new table opens during shutdown, primary async open, follower isolation, and remote compaction. Linux Buck builds and focused tests passed. Cross-platform CI is pending, and `make check-sources` cannot run successfully in this Sapling checkout because its script requires Git.

Reviewed By: pdillinger

Differential Revision: D122417547

fbshipit-source-id: 91d408469c35c4ea21165c5e7db75068e65c2389
2026-10-02 12:21:46 -07:00
Xingbo Wang
11516577ab Pass blob file checksums through blob file opens (#15268)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15268

Why this is required: remote file systems need an immutable blob-file checksum and checksum-function name when RocksDB opens a finalized blob file. This lets the file system distinguish file generations and safely validate or key cached extents.

Previous behavior: integrated BlobDB opened normal read-path blob files with the column family's ordinary FileOptions. Although finalized checksum metadata was stored in BlobFileMetaData and BlobFileAddition, it was not propagated through point reads, range reads, MultiGet, retry opens, or recovery verification. Delayed reads of direct-write files could also cache a finalized file reader opened without metadata.

New behavior: every finalized integrated BlobDB file open receives its checksum value and checksum-function name through FileOptions. Active direct-write files continue to use empty checksum fields until finalization. Delayed reads pinned to a pre-flush SuperVersion use the finalized metadata once the file has been sealed.

Implementation: add internal BlobFileOpenInfo transport across Version, BlobSource, and BlobFileCache. Populate it from version metadata and recovery additions. At the actual cache miss/open, copy the base FileOptions and set both checksum fields. Direct-write sealing registers owned checksum metadata with BlobFileCache, atomically evicts footer-less readers, and prevents a racing pre-seal refresh from repopulating the cache without metadata. Metadata is released after write-path ownership and old-memtable protection end.

Safety boundaries: this does not change public APIs, persisted formats, or blob cache keys. Cache hits do not copy checksum strings. Files with no generated checksum, including active direct-write files, retain empty checksum fields. Existing footer-skip, corruption, and reader-refresh behavior remains in place. Integration in downstream file systems is outside this change.

Tests and known limitations: filesystem-capture tests cover regular blob reads and delayed direct-write reads. After rebasing onto the latest master, blob_file_cache_test, blob_source_test, db_blob_basic_test, and db_blob_direct_write_test passed both normally and with ASSERT_STATUS_CHECKED=1 (95 tests in each configuration). Fast arc lint passed. make format-auto and make check-sources could not operate because their scripts assume a Git checkout while this checkout uses Sapling; all files in the patch were formatted directly with clang-format.

Reviewed By: chaitanyadatye, anand1976

Differential Revision: D121630172

fbshipit-source-id: 601d1097e4a3caa60f0d9ba1794e78e81855980c
2026-09-30 14:55:26 -07:00
Xingbo Wang
e6a2ee0bd2 Fix subset checkpoints with incomplete MANIFEST tails (#15123)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15123

Subset checkpoint post-processing appends column-family drop records to a copied MANIFEST. Recovery can tolerate an incomplete atomic group at the tail while retaining the reader high-water size, so appending at that size can produce a checkpoint that fails recovery.

Track the valid logical append boundary together with its MANIFEST file number, refresh it after recovery and successful writes, reset it across reactive MANIFEST switches, and trim only subset-checkpoint copies before appending drop records. Whole-DB checkpoints and the source MANIFEST remain unchanged.

Reviewed By: anand1976

Differential Revision: D116449394

fbshipit-source-id: a162dd6a2558f0f9ec40d878ee83956a89df698b
2026-08-22 12:17:33 -07:00
Peter Dillinger
e8554f1b11 Faster and safer MANIFEST recovery for remote compaction (OpenAndCompact) (#15133)
Summary:
Faster and safer MANIFEST recovery for remote compaction (OpenAndCompact)
`DB::OpenAndCompact` (remote/distributed compaction) opens the target DB as a
secondary and reconstructs the LSM state from the MANIFEST before running the
requested compaction. Previously, point-in-time recovery would stat/open the
SST (and blob) files referenced by the MANIFEST to classify them found/missing
and materialize candidate versions, and eagerly load their table handlers.
That is (a) a lot of unnecessary file operations and open latency, especially
on remote/distributed storage, and (b) fragile: when a file referenced by the
MANIFEST but not an input to the compaction was momentarily unavailable to the
worker -- e.g. an obsolete file the primary had already deleted -- recovery
could fail the job (surfacing as an incomplete "no valid result") or roll back
to an earlier version, even though the compaction only needs its own input
files, which the primary keeps referenced for the job's duration. This was seen
as a flaky failure of CompactionServiceTest.BasicCompactions on aarch64, and
reproduces on x86 under COERCE_CONTEXT_SWITCH.

Efficiency + reliability: recovery for the OpenAndCompact path now trusts the
MANIFEST. It reconstructs the current version from FileMetaData without
stat-ing/opening files to classify them and without eagerly opening
candidate-version table handlers, so it does far fewer file operations and
never fails or rolls back over a file the compaction does not need. The
compaction's input files are opened (and unique-id verified) on demand as it
reads them.

Correctness hardening: trusting the MANIFEST means the worker's own (possibly
eventually-consistent) view of CURRENT/MANIFEST drives the reconstructed LSM
shape, which feeds correctness-critical decisions (Compaction::IsBottommostLevel
/ KeyNotExistsBeyondOutputLevel). A worker that read a stale CURRENT (older
MANIFEST), a truncated MANIFEST, or a MANIFEST with a corrupt/torn tail could
reconstruct against an older LSM shape and silently drop keys that should be
kept. To prevent this, the primary records the MANIFEST position (file number
and size) it scheduled the compaction from and passes it in
CompactionServiceInput as a floor. After recovery the worker compares the size
of the maximal *valid* prefix it reconstructed -- which stops at any corrupt or
torn record and at a partial atomic group at EOF, so tolerated tail garbage
cannot inflate it -- against that floor, and refuses to compact against an older
view (an older file number, or the same file number whose valid prefix is
shorter), returning Status::Incomplete so the CompactionService can fall back to
a local compaction. Accept-equal-or-later is safe by monotonicity: while the
inputs stay locked (being_compacted), a later view can only have moved data
further down, never resurrecting a shadowed value, so only an older view is
unsafe.

Single kill switch: both behaviors are bundled behind one signal and one
option. Presence of the floor on the request (min_manifest_file_number != 0)
couples on both trust-manifest recovery and the floor check in the worker;
absence reverts the worker to the original point-in-time recovery with no floor
check. A single mutable DBOption, remote_compaction_manifest_floor (default
on), gates whether the primary populates the floor, so it is the one escape
hatch that disables the entire new recovery path on a running DB via
SetDBOptions if it ever misbehaves. The new CompactionServiceInput fields are
wire-compatible in both directions (0 = not provided), so an old worker or an
old primary simply behaves as if the switch were off.

Follow-up: recovery is not yet strictly "open only the compaction's inputs". A
limited number of non-input files are still opened by the bounded file-property
sampling in Version::PrepareAppend -> UpdateAccumulatedStats (tolerating any
that are missing), which today populates input FileMetaData::num_entries for
compaction input-record-count verification. A natural follow-up is to record
the needed per-file info (e.g. num_entries) in the MANIFEST so the worker can
skip these auxiliary opens entirely; alternatively, source input num_entries
from the worker's own read of its input table properties. Relatedly, the floor
comparand is the recovered "maximal valid prefix" size, which today equals the
MANIFEST file size but is defined to stay correct if a future MANIFEST format
writes trailing padding/footer past the last record.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/15133

Test Plan:
Added tests in compaction_service_test.cc:
- RemoteCompactionMissingLowerFileTrustsManifest: a non-input file referenced
  by the MANIFEST is unavailable during a remote compaction; the job completes
  with correct results (fails without trust-manifest recovery). The underlying
  race also reproduces under COERCE_CONTEXT_SWITCH.
- RemoteCompactionManifestFloorRejectsStaleView: inflate the floor so the
  worker's recovered MANIFEST is below it; assert the worker rejects, the job
  falls back to local, and a below-output deleted key stays deleted (no silent
  resurrection).
- RemoteCompactionManifestFloorSendsPosition: a non-zero floor is attached and
  the worker accepts its equal-or-later view.
- RemoteCompactionManifestFloorKillSwitchOff: with the option off, no floor is
  sent, the worker uses the original recovery, and a transiently-missing
  non-input file makes the job fail/roll back (the escape hatch reverts
  behavior).
- RemoteCompactionManifestFloorMutable: SetDBOptions flips the option; the
  floor stops being attached and the worker skips the check.
options_settable_test covers the new mutable DBOption.

Crash test: remote compaction is already exercised (db_crashtest randomly
enables remote_compaction_worker_threads, driving DB::OpenAndCompact), so with
remote_compaction_manifest_floor defaulting on, the new recovery path is
covered by the crash test by default -- no new crash-test plumbing is needed.
The kill switch is intentionally left un-randomized (always on): turning it off
re-enables the original, occasionally-broken recovery, which would only add
noisy failures for no benefit.

UPDATE: crash test is not well covered because of `"remote_compaction_failure_fall_back_to_local": 1` which is masking other existing failures. Addressing this is a high-priority follow-up item. (Not practical to fix in this diff.)

Reviewed By: jaykorean

Differential Revision: D116738823

Pulled By: pdillinger

fbshipit-source-id: c02e0a437d62fc526dbbfcf70edf43434dfc7c1f
2026-08-20 16:07:48 -07:00
Andrei Preda
b616b203b8 Drop flushed WAL data from the secondary's active memtable (#15066)
Summary:
Fix https://github.com/facebook/rocksdb/issues/15051: a secondary serves stale reads because entries replayed from a WAL the primary has since flushed are never evicted from the active memtable. During TryCatchUpWithPrimary(), seal the active memtable once the installed Version provably covers everything it holds, so the following RemoveOldMemTables() call drops it. Every memtable-dropping decision takes that same watermark, so a file set the secondary cannot read never turns the stale read into a vanished key.

## Why and How

A secondary replays the primary's WALs into its active memtable and stops replaying a WAL once the primary flushes it. Entries already replayed stayed behind, and since reads consult the memtable first, they shadowed the newer flushed values indefinitely. Iterators go stale too once bottommost compaction rewrites the flushed entry's sequence number to 0; until then Get() and an iterator disagree.

Seal the active memtable during catch-up, gated on the installed Version: each point-in-time Version now carries the column family's log number it reflects, exposed via the new
ReactiveVersionSet::GetInstalledVersionLogNumber(). Sealing requires cf_id_to_current_log_[cfd->GetID()] < that number, which guarantees the primary flushed everything the memtable holds (unflushed WAL data is kept) and that the flushed data is readable through the installed Version. The gate asks the Version directly because proxies fail: the log number alone advances even when no Version was installed, and "no missing files" misses atomic_flush groups parked by a sibling's missing file and corrupt-but-present files with
verify_sst_unique_id_in_manifest=false. In those cases the memtable holds the only readable copy, so dropping it would turn a stale read into a vanished key; the gate fails closed and keeps it.

Reconcile every initialized column family, not just cfds_changed: a round that failed after advancing the log number leaves a stale memtable that later rounds see no new MANIFEST record for. It can also leave a collectible immutable memtable, so the loop consults the new O(1) MemTableList::HasOldMemTablesToRemove() before skipping a column family. The predicate keeps the skip precise: reconciling any column family with a non-empty immutable list would be correct but wasteful, installing a fresh SuperVersion every catch-up call for memtables legitimately waiting on a primary flush and costing readers a mutex acquisition each time. With it, no extra super versions are installed in the steady state. That predicate and the RemoveOldMemTables() cutoff take the installed Version's log number as well, not cfd->GetLogNumber(): that advances as soon as the flush record is read, so an immutable memtable sealed on a WAL switch could otherwise be freed while the flushed file superseding it is unreadable. A sealed memtable is stamped with cf_id_to_current_log_[cfd->GetID()] + 1, the log number following its contents.

cf_id_to_current_log_ is keyed by column family id rather than ColumnFamilyData*, because ids are never reused while a dropped column family's pointer can be recycled, and it is recorded before WriteBatchInternal::InsertInto() rather than after: a batch stops at its first failure with earlier entries already inserted, so recording afterwards could leave the map naming an older WAL than the memtable holds. While the watermark lags and uncollectible memtables accumulate, the secondary warns, since it has no write path to enforce max_write_buffer_number.

The seal sequence, shared with RecoverLogFiles() and the follower's TryCatchUpWithLeader(), is extracted into
DBImplSecondary::SealActiveMemtable(). The follower is refactored onto it with no behaviour change: it keeps cfd->GetLogNumber() as its cutoff because that catch-up path never replays WALs, so its memtables hold nothing that only a not-yet-installed Version could make readable.

## Testing

New tests in db_secondary_test cover: the stale read via both Get() and an iterator, before and after bottommost compaction; unflushed WAL-only data surviving sealing, including two column families sharing a WAL; no data loss with a missing, atomic_flush-sibling-missing, or corrupt flushed file; an immutable memtable sealed on a WAL switch surviving an unreadable flushed file; a batch rejected partway through replay leaving the recorded WAL no older than the memtable's contents; and reconciliation after a failed round (injected via FaultInjectionTestFS at a sync point). Each mechanism was individually neutralized and confirmed to fail its test.

Verified with build_tools/rocksptest.sh over db_secondary_test, db_follower_test, memtable_list_test, version_set_test and version_edit_test (all pass, also under ASSERT_STATUS_CHECKED=1), plus db_basic_test, corruption_test, repair_test and db_flush_test; the secondary tests also ran 20x under COERCE_CONTEXT_SWITCH=1 with no flakes. make format-auto and make check-sources are clean.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/15066

Reviewed By: jaykorean, anand1976

Differential Revision: D115317523

Pulled By: xingbowang

fbshipit-source-id: a1d4615eb951d75e69ed242731336485c0dfa137
2026-08-17 13:47:30 -07:00
Peter Dillinger
1eb4a6e3e1 Rocksdb Secondary Cache Test failed: assertion failed - corruption: corrupted atomic group The file (#15000)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/15000

Reviewed By: xingbowang

Differential Revision: D113225538

Pulled By: pdillinger

fbshipit-source-id: fea9a671e9291ed030c5396264734195b2fb78bf
2026-07-24 08:30:27 -07:00
Peter Dillinger
c9536aaef7 Fix quadratic point-in-time MANIFEST recovery in VersionBuilder (#14929)
Summary:
Point-in-time MANIFEST replay -- best-efforts recovery (VersionSet::TryRecoverFromOneManifest) and secondary/follower catch-up (ManifestTailer) -- was quadratic in the number of MANIFEST records.

d458331ee (D61171320, "Move file tracking in VersionEditHandlerPointInTime to VersionBuilder") took a clean approach: it consolidated applying a VersionEdit and checking Version completeness into a single VersionBuilder implementation, so those checks were no longer duplicated between the handler and the builder. To let VersionEditHandlerPointInTime still build a Version reflecting the state before a valid->invalid edit, it added a save point -- but that save point proved inefficient: it was implemented by deep-copying the entire VersionBuilder::Rep before every edit (all of levels_[].added_files with a ref bump per file, table_file_levels_, found_files_, mutable_blob_file_metas_, ...). With N edits accumulating O(F) live files that is O(N*F) time and memory, and in the common healthy case the copy is pure waste since no Version is built during replay.

D110842287 (66bccb467, "Store BySmallestKey by value to avoid shared_ptr atomic copy in Rep") addressed a CPU-overhead symptom that had been misattributed to the shared_ptr atomic copies in that per-edit Rep copy. The real expense was copying Rep's containers -- notably table_file_levels_ -- on every edit. This change keeps d458331ee's clean single-implementation design but makes the save point cheap, removing the copy entirely:

- Replace the whole-Rep save point with a single-edit undo. Apply() records a compact, self-inverse undo of just the current edit (the pre-edit value of each touched key), and the PIT handler builds the pre-edit Version by rolling that one edit back, then redoing it to continue replay. This is O(edit) per edit, single-copy memory, and adds no extra file-verification I/O except on the rare valid->invalid negative edge. Also removes the Rep copy constructor.

- Store the undo registries in UnorderedMap (hash map) where ordering is not needed, which reduces the remaining per-edit CPU further. added_files and deleted_files keep an ordered map keyed by (level, file number), which trivial moves (same file number at two levels in one edit) require.

- Group the scalar/flag state mutated during Apply into a MutableScalars base so the undo can snapshot/restore it with a single copy/swap without duplicating the field list. Add util/cast_util.h up_cast<Base> for the explicit, compile-time-checked upcasts this uses instead of raw static_cast.

- Generalize D110842287: also store the stateless L0 comparators level_zero_cmp_by_epochno_ and level_zero_cmp_by_seqno_ by value rather than shared_ptr, dropping their make_shared allocation and atomic refcounting.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/14929

Test Plan: Debug build (asserts + force_consistency_checks on). The single-edit rollback path is exercised by the existing recovery coverage, all passing: version_builder_test, version_set_test, db_secondary_test (ManifestTailer), db_follower_test (PartialVersionRecovery = the negative-edge rebuild), and the db_basic_test best-efforts suite -- including BestEffortsRecoverIncompleteVersion with blob-file variants (blob addition rolled back/redone) and BestEffortRecoveryFailureWithTableCacheUseAfterFree (FileMetaData/table-cache lifecycle) -- plus corruption_test.

Reviewed By: joshkang97

Differential Revision: D111753669

Pulled By: pdillinger

fbshipit-source-id: 7e6b5238f55cd906b1d4ff0044aeb0a02ec1cdcd
2026-07-15 13:34:03 -07:00
Peter Dillinger
87c554b492 Persist compacted manifest size for auto-tuning across DB::Open (#14725)
Summary:
last_compacted_manifest_file_size_ drives TuneMaxManifestFileSize() to compute the manifest rotation threshold, but it started at 0 on every DB::Open and was only populated after the first manifest rotation. This is really only a problem with reuse_manifest_on_open, because no fresh manifest is created on open.

Add a new forward-compatible (safe-to-ignore) MANIFEST tag kLastCompactedManifestFileSize that records the approximate compacted manifest size at the end of WriteCurrentStateToManifest. During recovery, the value is loaded and used to immediately tune the rotation threshold.

The record includes a rough estimate of its own overhead (~15 bytes) and must be the last record written by WriteCurrentStateToManifest for accurate estimation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/14725

Test Plan:
Extended AutoTuneManifestSize in db_etc3_test to close and reopen with reuse_manifest_on_open after establishing a known auto-tuning state. Verifies that the manifest file number is preserved (no spurious rotation) and that subsequent CF additions don't trigger rotation -- proving the persisted compacted size keeps the tuned threshold correct. Verified the test fails when the recovery loading is disabled.

Relax a fragile Java test that was dependent on the exact size of the manifest file.

SHORT_TEST=1 ./tools/check_format_compatible.sh

Reviewed By: anand1976

Differential Revision: D104464522

Pulled By: pdillinger

fbshipit-source-id: 4f5d22d2e149bd40a523ee11780e5e3344803c19
2026-05-13 18:31:49 -07:00
Anand Ananthabhotla
c734b7cc60 Add reuse_manifest_on_open DBOption (#14704)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/14704

Add an immutable DBOption `reuse_manifest_on_open` (default false). When enabled, `DB::Open` can keep using the recovered MANIFEST for the first post-open metadata update instead of rebuilding a fresh MANIFEST, which can reduce warm-open latency for DBs whose MANIFEST is expensive to regenerate.

Reuse is still best-effort. If RocksDB cannot safely resume appending to the recovered MANIFEST, it falls back to the existing fresh-MANIFEST path. The option is also disabled under `best_efforts_recovery`.

This diff also teaches the reopened MANIFEST writer to adopt the existing file size before appending, documents the small-`max_manifest_file_size` caveat for the reused path, and keeps the full warm-reopen composition working with `optimize_manifest_for_recovery`.

Reviewed By: hx235, pdillinger

Differential Revision: D103568447

fbshipit-source-id: f4f5c35ea3ef0b80a0d52d94be40c6bd11505999
2026-05-07 13:10:59 -07:00
Maciej Szeszko
799079cac5 Handle drop column family version edit in file checksum retriever (#13832)
Summary:
... by ensuring that files in dropped column family are not returned to the caller upon successful, offline MANIFEST iteration.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13832

Test Plan: `DBTest2, GetFileChecksumsFromCurrentManifest_CRC32`

Reviewed By: pdillinger

Differential Revision: D79607298

Pulled By: mszeszko-meta

fbshipit-source-id: e7948e086ba6e6fb953a3959fdcc81300613d73e
2025-08-05 10:48:49 -07:00
Hui Xiao
37a26591c7 Print note about the large hard-coded num_level for manifest dump (#13681)
Summary:
**Context/Summary:**
Since LDB manifest dump including printing the LSM shape does not open the db and manifest itself does not have info about Options.num_levels, LDB tool (the only caller of `DumpManifestHandler` has to set a "hopefully-large-enough" level number (i.e,64) to print info of every level for the LSM shape in the manifest. This can mislead whoever that's reading the manifest to believe there are actually 64 levels configured with the CF. This PR clarifies that.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13681

Test Plan:
Manual test
`./ldb  manifest_dump --hex --verbose --json --path=<some manifest file path>`
```
--------------- Column family "9"  (ID 9) --------------
log number: 115873
comparator: leveldb.BytewiseComparator
 --- level 0 --- version# 19 ---
 --- level 1 --- version# 19 --- compact_cursor: '000000000000000900000000000000DF78787878787878' seq:3418519, type:2 ---
 --- level 2 --- version# 19 --- compact_cursor: '000000000000000900000000000000D8' seq:3446619, type:2 ---
 --- level 3 --- version# 19 --- compact_cursor: '000000000000000900000000000000DF78787878787878' seq:3418519, type:2 ---
 --- level 4 --- version# 19 --- compact_cursor: '000000000000000900000000000000DF78787878787878' seq:3418519, type:2 ---
 --- level 5 --- version# 19 --- compact_cursor: '0000000000000009000000000000012B0000000000000065' seq:3447830, type:2 ---
 --- level 6 --- version# 19 ---
 115931:376281[0 .. 0]['0000000000000000' seq:0, type:1 .. '00000000000003E7000000000000012B00000000000002B1' seq:0, type:1]
 --- level 7 --- version# 19 ---
 --- level 8 --- version# 19 ---
 --- level 9 --- version# 19 ---
 --- level 10 --- version# 19 ---
 --- level 11 --- version# 19 ---
....
 --- level 61 --- version# 19 ---
 --- level 62 --- version# 19 ---
 --- level 63 --- version# 19 ---
By default, manifest file dump prints LSM trees as if 64 levels were configured, which is not necessarily true for the column family (CF) this manifest is associated with. Please consult other DB files, such as the OPTIONS file, to confirm.

```

Reviewed By: jaykorean

Differential Revision: D76391064

Pulled By: hx235

fbshipit-source-id: 3e1c58e0eeb39a5fa020040201b07b181f8977a6
2025-06-11 17:14:14 -07:00
Peter Dillinger
b9c7481fc2 Fix some secondary/read-only DB logic (#13441)
Summary:
Primarily, fix an issue from https://github.com/facebook/rocksdb/issues/13316 with opening secondary DB with preserve/preclude option (crash test disable in https://github.com/facebook/rocksdb/issues/13439). The issue comes down to mixed-up interpretations of "read_only" which should now be resolved. I've introduced the stronger notion of "unchanging" which means the VersionSet never sees any changes to the LSM tree, and the weaker notion of "read_only" which means LSM tree changes are not written through this VersionSet/etc. but can pick up externally written changes. In particular, ManifestTailer should use read_only=true (along with unchanging=false) for proper handling of preserve/preclude options.

A new assertion in VersionSet::CreateColumnFamily to help ensure sane usage of the two boolean flags is incompatible with the known wart of allowing CreateColumnFamily on a read-only DB. So to keep that assertion, I have fixed that issue by disallowing it. And this in turn required downstream clean-up in ldb, where I cleaned up some call sites as well.

Also, rename SanitizeOptions for ColumnFamilyOptions to SanitizeCfOptions, for ease of search etc.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13441

Test Plan:
* Added preserve option to a test in db_secondary_test, which reproduced the failure seen in the crash test.
* Revert https://github.com/facebook/rocksdb/issues/13439 to re-enable crash test functionality
* Update some tests to deal with disallowing CF creation on read-only DB
* Add some testing around read-only DBs and CreateColumnFamily(ies)
* Resurrect a nearby test for read-only DB to be sure it doesn't write to the DB dir. New EnforcedReadOnlyReopen should probably be used in more places but didn't want to attempt a big migration here and now. (Suggested follow-up.)

Reviewed By: jowlyzhang

Differential Revision: D70808033

Pulled By: pdillinger

fbshipit-source-id: 486b4e9f9c9045150a0ebb9cb302753d03932a3f
2025-03-07 14:56:45 -08:00
Peter Dillinger
da8eba8b49 Improve consistency of SeqnoToTime tracking in SuperVersion (#13316)
Summary:
This is an unexpectedly complex follow-up to https://github.com/facebook/rocksdb/issues/13269.

This change solves (and detects regressed) inconsistencies between whether a CF's SuperVersion is configured with a preserve/preclude option and whether it gets a usable SeqnoToTimeMapping. Operating with preserve/preclude and no usable mapping is degraded functionality we need to avoid. And no mapping is useful for actually disabling the feature (except with respect to existing SST files, but that's less of a concern for now).

The challenge is that how we maintain the DB's SeqnoToTimeMapping can depend on all the column families, and we don't want to iterate over all column families *for each column family* (e.g. on initially creating each). The existing code was a bit relaxed:
* On initially creating or re-configuring a CF, we might install an empty mapping, but soon thereafter (after releasing and re-acquiring the DB mutex) re-install another SuperVersion with a useful mapping.

The solution here is to refactor the logic so that there's a distinct but related workflow for (a) ensuring a quality set of mappings when we might only be considering a single CF (`EnsureSeqnoToTimeMapping()`), and (b) massaging that set of mappings to account for all CFs (`RegisterRecordSeqnoTimeWorker`) which doesn't need to re-install new SuperVersions because each CF already has good mappings and will get updated SuperVersions when the periodic task adds new mappings. This should eliminate the extra SuperVersion installs associated with preserve/preclude on CF creation or re-configure, making it the same as any other CF.

Some more details:
* Some refactorings such as removing new_seqno_to_time_mapping from SuperVersionContext. (Now use parameter instead of being stateful.)
* Propagate `read_only` aspect of DB to more places so that we can pro-actively disable preserve/preclude on read-only DBs, so that we don't run afoul of the assertion expecting SeqnoToTime entries.
* Introduce a utility struct `MinAndMaxPreserveSeconds` for aggregating preserve/preclude settings in a useful way, sometimes on one CF and sometimes across multiple CFs. Much cleaner! (IMHO)
* Introduce a function `InstallSuperVersionForConfigChange` that is a superset of `InstallSuperVersionAndScheduleWork` for when a CF is new or might have had a change to its mutable options.
* Eliminate redundant re-install SuperVersions of created "missing" CFs in DBImpl::Open.

Intended follow-up:
* Ensure each flush has an "upper bound" SeqnoToTime entry, which would resolve a FIXME in tiered_compaction_test, but causes enough test churn to deserve its own PR + investigation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13316

Test Plan:
This change is primarily validated by a new assertion in SuperVersion::Init to ensure consistency between (a) presence of any SeqnoToTime mappings in the SuperVersion and (b) preserve/preclude option being currently set.

One unit test update was needed because we now ensure at least one SeqnoToTime entry is created on any DB::Open with preserve/preclude, so that there is a lower bound time on all the future data writes. This required a small hack in associating the time with Seqno 1 instead of 0, which is reserved for "unspecified old."

Reviewed By: cbi42

Differential Revision: D70540638

Pulled By: pdillinger

fbshipit-source-id: bb419fdbeb5a1f115fc429c211f9b8efaf2f56d7
2025-03-04 17:44:01 -08:00
Peter Dillinger
780280b52e Reduce unnecessary MutableCFOptions copies and parameters (#13301)
Summary:
As follow-up to https://github.com/facebook/rocksdb/issues/13239, this change is primarily motivated by simplifying the calling conventions of LogAndApply. Since it must be called while holding the DB mutex, it can read safely read cfd->GetLatestMutableCFOptions(), until it releases the mutex within ProcessManifestWrites. Before it releases the mutex, it makes a copy of the mutable options in a new, unpublished Version object, which can be used when not holding the DB mutex. This eliminates the need for callers of LogAndApply to copy mutable options for its sake, or even specify mutable options at all. And it eliminates the need for *another* copy to be saved in ManifestWriter.

Other functions that don't need the mutable options parameter:
* ColumnFamilyData::CreateNewMemtable()
* CompactionJob::Install() / InstallCompactionResults()
* MemTableList::*InstallMemtable*()
* Version::PrepareAppend()

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13301

Test Plan: existing tests, CI with sanitizers

Reviewed By: mszeszko-meta

Differential Revision: D68234865

Pulled By: pdillinger

fbshipit-source-id: 6ce95f9cc479834e09ffc8ce93cbae7b664329e5
2025-01-16 14:10:11 -08:00
Peter Dillinger
b3333587eb Clean up some CFOptions code hygiene, fix SetOptions() bug (#13294)
Summary:
To start, I wanted to remove the unnecessary new_options parameter of `InstallSuperVersionAndScheduleWork()`. Passing it something other than the latest mutable options would be inconsistent/outdated. There was even a comment "Use latest MutableCFOptions" on a place that was using the saved options in effect for the compaction.

On investigation, this fixes an undiagnosed but longstanding serious bug in SetOptions() where the new settings can be reverted if a flush or compaction started before the SetOptions() finishes after. Fix confirmed with new unit test in db_test.cc.

I also got tired of seeing the cumbersome usage of pointer rather than const reference for related options accesses, so there's kind of a large (but trivial) refactoring tied in here as well. (Sorry for combining them; wasn't planning a major bug fix)

Intended follow-up: Clarify/simplify the crazy calling conventions of LogAndApply, and remove some unnecessary copying of MutableCFOptions (see new FIXMEs)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13294

Test Plan: test for bug fix, confirmed fails on main and at least as far back as version 8.10. Plus existing tests and CI

Reviewed By: mszeszko-meta

Differential Revision: D68141563

Pulled By: pdillinger

fbshipit-source-id: f6c3290145afa06cc2fe8b485a5de17560a5deea
2025-01-15 13:11:40 -08:00
Peter Dillinger
ac24f152a1 Refactor table_factory into MutableCFOptions (#13077)
Summary:
This is setting up for a fix to a data race in SetOptions on BlockBasedTableOptions (BBTO), https://github.com/facebook/rocksdb/issues/10079
The race will be fixed by replacing `table_factory` with a modified copy whenever we want to modify a BBTO field.

An argument could be made that this change creates more entaglement between features (e.g. BlobSource <-> MutableCFOptions), rather than (conceptually) minimizing the dependencies of each feature, but
* Most of these things already depended on ImmutableOptions
* Historically there has been a lot of plumbing (and possible small CPU overhead) involved in adding features that need to reach a lot of places, like `block_protection_bytes_per_key`. Keeping those wrapped up in options simplifies that.
* SuperVersion management generally takes care of lifetime management of MutableCFOptions, so is not that difficult. (Crash test agrees so far.)

There are some FIXME places where it is known to be unsafe to replace `block_cache` unless/until we handle shared_ptr tracking properly. HOWEVER, replacing `block_cache` is generally dubious, at least while existing users of the old block cache (e.g. table readers) can continue indefinitely.

The change to cf_options.cc is essentially just moving code (not changing).

I'm not concerned about the performance of copying another shared_ptr with MutableCFOptions, but I left a note about considering an improvement if more shared_ptr are added to it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13077

Test Plan:
existing tests, crash test.

Unit test DBOptionsTest.GetLatestCFOptions updated with some temporary logic. MemoryTest required some refactoring (simplification) for the change.

Reviewed By: cbi42

Differential Revision: D64546903

Pulled By: pdillinger

fbshipit-source-id: 69ae97ce5cf4c01b58edc4c5d4687eb1e5bf5855
2024-10-17 14:13:20 -07:00
Yu Zhang
295326b6ee Best efforts recovery recover seqno prefix (#12938)
Summary:
This PR make best efforts recovery more permissive by allowing it to recover incomplete Version that presents a valid point in time view from the user's perspective. Currently, a Version is only valid and saved if all files consisting that Version can be found. With this change, if only a suffix of L0 files (and their associated blob files) are missing,  a valid Version is also available to be saved and recover to. Note that we don't do this if the column family was atomically flushed. Because atomic flush also need a consistent view across the column families, we cannot guarantee that if we are recovering to incomplete version.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12938

Test Plan: Existing tests and added unit tests.

Reviewed By: anand1976

Differential Revision: D61414381

Pulled By: jowlyzhang

fbshipit-source-id: f9b73deb34d35ad696ab42315928b656d586262a
2024-08-16 17:18:54 -07:00
Yu Zhang
d458331ee9 Move file tracking in VersionEditHandlerPointInTime to VersionBuilder (#12928)
Summary:
`VersionEditHandlerPointInTime` is tracking found files, missing files, intermediate files in order to decide to build a `Version` on negative edge trigger (transition from valid to invalid) without applying  the current `VersionEdit`.  However, applying `VersionEdit` and check completeness of a `Version` are specialization of `VersionBuilder`.  More importantly, when we augment best efforts recovery to recover not just complete point in time Version but also a prefix of seqno for a point in time Version, such checks need to be duplicated in `VersionEditHandlerPointInTime` and `VersionBuilder`.

To avoid this, this refactor move all the file tracking functionality in `VersionEditHandlerPointInTime` into `VersionBuilder`.  To continue to let `VersionEditHandlerPIT` do the edge trigger check and  build a `Version` before applying the current `VersionEdit`, a suite of APIs to supporting creating a save point and its associated functions are added in `VersionBuilder` to achieve this.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12928

Test Plan: Existing tests

Reviewed By: anand1976

Differential Revision: D61171320

Pulled By: jowlyzhang

fbshipit-source-id: 604f66f8b1e3a3e13da59d8ba357c74e8a366dbc
2024-08-12 21:09:37 -07:00
anand76
0ed93552f4 Implement obsolete file deletion (GC) in follower (#12657)
Summary:
This PR implements deletion of obsolete files in a follower RocksDB instance. The follower tails the leader's MANIFEST and creates links to newly added SST files. These links need to be deleted once those files become obsolete in order to reclaim space. There are three cases to be considered -
1. New files added and links created, but the Version could not be installed due to some missing files. Those links need to be preserved so a subsequent catch up attempt can succeed. We insert the next file number in the `VersionSet` to `pending_outputs_` to prevent their deletion.
2. Files deleted from the previous successfully installed `Version`. These are deleted as usual in `PurgeObsoleteFiles`.
3. New files added by a `VersionEdit` and deleted by a subsequent `VersionEdit`, both processed in the same catchup attempt. Links will be created for the new files when verifying a candidate `Version`. Those need to be deleted explicitly as they're never added to `VersionStorageInfo`, and thus not deleted by `PurgeObsoleteFiles`.

Test plan -
New unit tests in `db_follower_test`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12657

Reviewed By: jowlyzhang

Differential Revision: D57462697

Pulled By: anand1976

fbshipit-source-id: 898f15570638dd4930f839ffd31c560f9cb73916
2024-05-17 19:13:33 -07:00
Andrew Kryczka
27a2473668 Best-effort recovery support for atomic flush (#12406)
Summary:
This PR updates `VersionEditHandlerPointInTime` to recover all or none of the updates in an AtomicGroup. This makes best-effort recovery properly handle atomic flushes during recovery, so the features are now allowed to both be enabled at once.

The new logic requires that AtomicGroups do not contain column family additions or removals. AtomicGroups are currently written for atomic flush, which does not include such edits.

Column family additions or removals are recovered independently of AtomicGroups. The new logic needs to be aware of removal, though, so that a dropped CF does not prevent completion of an AtomicGroup recovery.

The new logic treats each AtomicGroup as if it contains updates for all existing column families, even though it is possible to create AtomicGroups that only affect a subset of column families. This simplifies the logic at the expense of recovering less data in certain edge case scenarios.

The usage of `MaybeCreateVersion()` is pretty tricky. The goal is to create a barrier at the start of an AtomicGroup such that all valid states up to that point will be applied to `versions_`. Here is a summary.

- `MaybeCreateVersion(..., false)` creates a `Version` on a negative edge trigger (transition from valid to invalid). It was  previously called when applying each update. Now, it is only called when applying non-AtomicGroup updates.
- `MaybeCreateVersion(..., true)` creates a `Version` on a positive level trigger (valid state). It was previously called only at the end of iteration. Now, it is additionally called before processing an AtomicGroup.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12406

Reviewed By: jaykorean, cbi42

Differential Revision: D54494904

Pulled By: ajkr

fbshipit-source-id: 0114a9fe1d04b471d086dcab5978ea8a3a56ad52
2024-03-06 14:40:40 -08:00
Yu Zhang
071a146fa0 Add support for range deletion when user timestamps are not persisted (#12254)
Summary:
For the user defined timestamps in memtable only feature, some special handling for range deletion blocks are needed since both the key (start_key) and the value (end_key) of a range tombstone can contain user-defined timestamps. Handling for the key is taken care of in the same way as the other data blocks in the block based table. This PR adds the special handling needed for the value (end_key) part. This includes:

1) On the write path, when L0 SST files are first created from flush, user-defined timestamps are removed from an end key of a range tombstone. There are places where it's logically removed (replaced with a min timestamp) because there is still logic with the running comparator that expects a user key that contains timestamp. And in the block based builder, it is eventually physically removed before persisted in a block.

2) On the read path, when range deletion block is being read, we artificially pad a min timestamp to the end key of a range tombstone in `BlockBasedTableReader`.

3) For file boundary `FileMetaData.largest`, we artificially pad a max timestamp to it if it contains a range deletion sentinel. Anytime when range deletion end_key is used to update file boundaries, it's using max timestamp instead of the range tombstone's actual timestamp to mark it as an exclusive end. d69628e6ce/db/dbformat.h (L923-L935)
This max timestamp is removed when in memory `FileMetaData.largest` is persisted into Manifest, we pad it back when it's read from Manifest while handling related `VersionEdit` in `VersionEditHandler`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12254

Test Plan: Added unit test and enabled this feature combination's stress test.

Reviewed By: cbi42

Differential Revision: D52965527

Pulled By: jowlyzhang

fbshipit-source-id: e8315f8a2c5268e2ae0f7aec8012c266b86df985
2024-01-29 11:37:34 -08:00
Yu Zhang
4b013dcbed Remove VersionEdit's friends pattern (#12024)
Summary:
Almost each of VersionEdit private member has its own getter and setter. Current code access them with a combination of directly accessing private members and via getter and setters. There is no obvious benefits to have this pattern except potential performance gains. I tried this simple benchmark for removing the friends pattern completely, and there is no obvious regression. So I think it would good to remove VersionEdit's friends completely.

```TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num_column_families=10 -num=50000000```

With change:
fillseq      :       2.994 micros/op 333980 ops/sec 149.710 seconds 50000000 operations;   36.9 MB/s
fillseq      :       3.033 micros/op 329656 ops/sec 151.673 seconds 50000000 operations;   36.5 MB/s
fillseq      :       2.991 micros/op 334369 ops/sec 149.535 seconds 50000000 operations;   37.0 MB/s
Without change:
fillseq      :       3.015 micros/op 331715 ops/sec 150.732 seconds 50000000 operations;   36.7 MB/s
fillseq      :       3.044 micros/op 328553 ops/sec 152.182 seconds 50000000 operations;   36.3 MB/s
fillseq      :       3.091 micros/op 323520 ops/sec 154.550 seconds 50000000 operations;   35.8 MB/s

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12024

Reviewed By: pdillinger

Differential Revision: D50806066

Pulled By: jowlyzhang

fbshipit-source-id: 35d287ce638a38c30f243f85992e615b4c90eb27
2023-11-01 12:04:11 -07:00
Yu Zhang
c24ef26ca7 Support switching on / off UDT together with in-Memtable-only feature (#11623)
Summary:
Add support to allow enabling / disabling user-defined timestamps feature for an existing column family in combination with the in-Memtable only feature.

To do this, this PR includes:
1) Log the `persist_user_defined_timestamps` option per column family in Manifest to facilitate detecting an attempt to enable / disable UDT. This entry is enforced to be logged in the same VersionEdit as the user comparator name entry.

2) User-defined timestamps related options are validated when re-opening a column family, including user comparator name and the `persist_user_defined_timestamps` flag. These type of settings and settings change are considered valid:
     a) no user comparator change and no effective `persist_user_defined_timestamp` flag change.
     b) switch user comparator to enable UDT provided the immediately effective `persist_user_defined_timestamps` flag
         is false.
     c) switch user comparator to disable UDT provided that the before-change `persist_user_defined_timestamps` is
         already false.
3) when an attempt to enable UDT is detected, we mark all its existing SST files as "having no UDT" by marking its `FileMetaData.user_defined_timestamps_persisted` flag to false and handle their file boundaries `FileMetaData.smallest`, `FileMetaData.largest` by padding a min timestamp.

4) while enabling / disabling UDT feature, timestamp size inconsistency in existing WAL logs are handled to make it compatible with the running user comparator.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11623

Test Plan:
```
make all check
./db_with_timestamp_basic_test --gtest-filter="*EnableDisableUDT*"
./db_wal_test --gtest_filter="*EnableDisableUDT*"
```

Reviewed By: ltamasi

Differential Revision: D47636862

Pulled By: jowlyzhang

fbshipit-source-id: dcd19f67292da3c3cc9584c09ad00331c9ab9322
2023-07-26 20:16:32 -07:00
Changyu Bi
854eb76a8c Improve error message when an SST file in MANIFEST is not found (#11573)
Summary:
I got the following error message when an SST file is recorded in MANIFEST but is missing from the db folder.
It's confusing in two ways:
1. The part about file "./074837.ldb" which RocksDB will attempt to open only after ./074837.sst is not found.
2. The last part about "No such file or directory in file ./MANIFEST-074507" sounds like `074837.ldb` is not found in manifest.

```
ldb --hex --db=. get some_key

Failed: Corruption: Corruption: IO error: No such file or directory: While open a file for random read: ./074837.ldb: No such file or directory in file ./MANIFEST-074507
```

Improving the error message a little bit:

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11573

Test Plan:
run the same command after this PR
```
Failed: Corruption: Corruption: IO error: No such file or directory: While open a file for random read: ./074837.sst: No such file or directory  The file ./MANIFEST-074507 may be corrupted.
```

Reviewed By: ajkr

Differential Revision: D47192056

Pulled By: cbi42

fbshipit-source-id: 06863f376cc4455803cffb2250c41399b4c39467
2023-07-10 15:52:38 -07:00
Yu Zhang
f74526341d Handle file boundaries when timestamps should not be persisted (#11578)
Summary:
Handle file boundaries `FileMetaData.smallest`, `FileMetaData.largest` for when `persist_user_defined_timestamps` is false:
    1) on the manifest write path, the original user-defined timestamps in file boundaries are stripped. This stripping is done during `VersionEdit::Encode` to limit the effect of the stripping to only the persisted version of the file boundaries.
    2) on the manifest read path during DB open, a a min timestamp is padded to the file boundaries. Ideally, this padding should happen during `VersionEdit::Decode` so that all in memory file boundaries have a compatible user key format as the running user comparator. However, because the user-defined timestamp size information is not available at that time. This change is added to `VersionEditHandler::OnNonCfOperation`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11578

Test Plan:
```
make all check
./version_edit_test --gtest_filter="*EncodeDecodeNewFile4HandleFileBoundary*".
./db_with_timestamp_basic_test --gtest_filter="*HandleFileBoundariesTest*"
```

Reviewed By: pdillinger

Differential Revision: D47309399

Pulled By: jowlyzhang

fbshipit-source-id: 21b4d54d2089a62826b31d779094a39cb2bbbd51
2023-07-10 11:03:25 -07:00
Changyu Bi
62fc15f009 Block per key-value checksum (#11287)
Summary:
add option `block_protection_bytes_per_key` and implementation for block per key-value checksum. The main changes are
1. checksum construction and verification in block.cc/h
2. pass the option `block_protection_bytes_per_key` around (mainly for methods defined in table_cache.h)
3. unit tests/crash test updates

Tests:
* Added unit tests
* Crash test: `python3 tools/db_crashtest.py blackbox --simple --block_protection_bytes_per_key=1 --write_buffer_size=1048576`

Follow up (maybe as a separate PR): make sure corruption status returned from BlockIters are correctly handled.

Performance:
Turning on block per KV protection has a non-trivial negative impact on read performance and costs additional memory.
For memory, each block includes additional 24 bytes for checksum-related states beside checksum itself. For CPU, I set up a DB of size ~1.2GB with 5M keys (32 bytes key and 200 bytes value) which compacts to ~5 SST files (target file size 256 MB) in L6 without compression. I tested readrandom performance with various block cache size (to mimic various cache hit rates):

```
SETUP
make OPTIMIZE_LEVEL="-O3" USE_LTO=1 DEBUG_LEVEL=0 -j32 db_bench
./db_bench -benchmarks=fillseq,compact0,waitforcompaction,compact,waitforcompaction -write_buffer_size=33554432 -level_compaction_dynamic_level_bytes=true -max_background_jobs=8 -target_file_size_base=268435456 --num=5000000 --key_size=32 --value_size=200 --compression_type=none

BENCHMARK
./db_bench --use_existing_db -benchmarks=readtocache,readrandom[-X10] --num=5000000 --key_size=32 --disable_auto_compactions --reads=1000000 --block_protection_bytes_per_key=[0|1] --cache_size=$CACHESIZE

The readrandom ops/sec looks like the following:
Block cache size:  2GB        1.2GB * 0.9    1.2GB * 0.8     1.2GB * 0.5   8MB
Main              240805     223604         198176           161653       139040
PR prot_bytes=0   238691     226693         200127           161082       141153
PR prot_bytes=1   214983     193199         178532           137013       108211
prot_bytes=1 vs    -10%        -15%          -10.8%          -15%        -23%
prot_bytes=0
```

The benchmark has a lot of variance, but there was a 5% to 25% regression in this benchmark with different cache hit rates.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11287

Reviewed By: ajkr

Differential Revision: D43970708

Pulled By: cbi42

fbshipit-source-id: ef98d898b71779846fa74212b9ec9e08b7183940
2023-04-25 12:08:23 -07:00
Hui Xiao
151242ce46 Group rocksdb.sst.read.micros stat by IOActivity flush and compaction (#11288)
Summary:
**Context:**
The existing stat rocksdb.sst.read.micros does not reflect each of compaction and flush cases but aggregate them, which is not so helpful for us to understand IO read behavior of each of them.

**Summary**
- Update `StopWatch` and `RandomAccessFileReader` to record `rocksdb.sst.read.micros` and `rocksdb.file.{flush/compaction}.read.micros`
   - Fixed the default histogram in `RandomAccessFileReader`
- New field `ReadOptions/IOOptions::io_activity`; Pass `ReadOptions` through paths under db open, flush and compaction to where we can prepare `IOOptions` and pass it to `RandomAccessFileReader`
- Use `thread_status_util` for assertion in `DbStressFSWrapper` for continuous testing on we are passing correct `io_activity` under db open, flush and compaction

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11288

Test Plan:
- **Stress test**
- **Db bench 1: rocksdb.sst.read.micros COUNT ≈ sum of rocksdb.file.read.flush.micros's and rocksdb.file.read.compaction.micros's.**  (without blob)
     - May not be exactly the same due to `HistogramStat::Add` only guarantees atomic not accuracy across threads.
```
./db_bench -db=/dev/shm/testdb/ -statistics=true -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3 (-use_plain_table=1 -prefix_size=10)
```
```
// BlockBasedTable
rocksdb.sst.read.micros P50 : 2.009374 P95 : 4.968548 P99 : 8.110362 P100 : 43.000000 COUNT : 40456 SUM : 114805
rocksdb.file.read.flush.micros P50 : 1.871841 P95 : 3.872407 P99 : 5.540541 P100 : 43.000000 COUNT : 2250 SUM : 6116
rocksdb.file.read.compaction.micros P50 : 2.023109 P95 : 5.029149 P99 : 8.196910 P100 : 26.000000 COUNT : 38206 SUM : 108689

// PlainTable
Does not apply
```
- **Db bench 2: performance**

**Read**

SETUP: db with 900 files
```
./db_bench -db=/dev/shm/testdb/ -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655  -disable_auto_compactions=true -target_file_size_base=655 -compression_type=none
```run till convergence
```
./db_bench -seed=1678564177044286 -use_existing_db=true -db=/dev/shm/testdb -benchmarks=readrandom[-X60] -statistics=true -num=1000000 -disable_auto_compactions=true -compression_type=none -bloom_bits=3
```
Pre-change
`readrandom [AVG 60 runs] : 21568 (± 248) ops/sec`
Post-change (no regression, -0.3%)
`readrandom [AVG 60 runs] : 21486 (± 236) ops/sec`

**Compaction/Flush**run till convergence
```
./db_bench -db=/dev/shm/testdb2/ -seed=1678564177044286 -benchmarks="fillseq[-X60]" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655  -disable_auto_compactions=false -target_file_size_base=655 -compression_type=none

rocksdb.sst.read.micros  COUNT : 33820
rocksdb.sst.read.flush.micros COUNT : 1800
rocksdb.sst.read.compaction.micros COUNT : 32020
```
Pre-change
`fillseq [AVG 46 runs] : 1391 (± 214) ops/sec;    0.7 (± 0.1) MB/sec`

Post-change (no regression, ~-0.4%)
`fillseq [AVG 46 runs] : 1385 (± 216) ops/sec;    0.7 (± 0.1) MB/sec`

Reviewed By: ajkr

Differential Revision: D44007011

Pulled By: hx235

fbshipit-source-id: a54c89e4846dfc9a135389edf3f3eedfea257132
2023-04-21 09:07:18 -07:00
Jaepil Jeong
969d4e1dd2 Fix compile errors in Clang due to unused variables depending on the build configuration (#11234)
Summary:
This PR fixes compilation errors in Clang due to unused variables like the below:
```
[109/329] Building CXX object CMakeFiles/rocksdb.dir/db/version_edit_handler.cc.o
FAILED: CMakeFiles/rocksdb.dir/db/version_edit_handler.cc.o
ccache /opt/homebrew/opt/llvm/bin/clang++ -DGFLAGS=1 -DGFLAGS_IS_A_DLL=0 -DHAVE_FULLFSYNC -DJEMALLOC_NO_DEMANGLE -DLZ4 -DOS_MACOSX -DROCKSDB_JEMALLOC -DROCKSDB_LIB_IO_POSIX -DROCKSDB_NO_DYNAMIC_EXTENSION -DROCKSDB_PLATFORM_POSIX -DSNAPPY -DTBB -DZLIB -DZSTD -I/Users/jaepil/work/deepsearch/deps/cpp/rocksdb -I/Users/jaepil/work/deepsearch/deps/cpp/rocksdb/include -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -I/Users/jaepil/app/include -I/opt/homebrew/include -I/opt/homebrew/opt/llvm/include -I/opt/homebrew/opt/llvm/include/c++/v1 -W -Wextra -Wall -pthread -Wsign-compare -Wshadow -Wno-unused-parameter -Wno-unused-variable -Woverloaded-virtual -Wnon-virtual-dtor -Wno-missing-field-initializers -Wno-strict-aliasing -Wno-invalid-offsetof -fno-omit-frame-pointer -momit-leaf-frame-pointer -march=armv8-a+crc+crypto -Wno-unused-function -Werror -O2 -g -DNDEBUG -arch arm64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.1.sdk -std=gnu++20 -MD -MT CMakeFiles/rocksdb.dir/db/version_edit_handler.cc.o -MF CMakeFiles/rocksdb.dir/db/version_edit_handler.cc.o.d -o CMakeFiles/rocksdb.dir/db/version_edit_handler.cc.o -c /Users/jaepil/work/deepsearch/deps/cpp/rocksdb/db/version_edit_handler.cc
/Users/jaepil/work/deepsearch/deps/cpp/rocksdb/db/version_edit_handler.cc:30:10: error: variable 'recovered_edits' set but not used [-Werror,-Wunused-but-set-variable]
  size_t recovered_edits = 0;
         ^
1 error generated.
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11234

Reviewed By: cbi42

Differential Revision: D43458604

Pulled By: ajkr

fbshipit-source-id: d8c50e1a108887b037a120cd9f19374ddaeee817
2023-03-09 16:42:57 -08:00
Hui Xiao
98d5db5c2e Sort L0 files by newly introduced epoch_num (#10922)
Summary:
**Context:**
Sorting L0 files by `largest_seqno` has at least two inconvenience:
-  File ingestion and compaction involving ingested files can create files of overlapping seqno range with the existing files. `force_consistency_check=true` will catch such overlap seqno range even those harmless overlap.
    - For example, consider the following sequence of events ("key@n" indicates key at seqno "n")
       - insert k1@1 to memtable m1
       - ingest file s1 with k2@2, ingest file s2 with k3@3
        - insert k4@4 to m1
       - compact files s1, s2 and  result in new file s3 of seqno range [2, 3]
       - flush m1 and result in new file s4 of seqno range [1, 4]. And `force_consistency_check=true` will think s4 and s3 has file reordering corruption that might cause retuning an old value of k1
    - However such caught corruption is a false positive since s1, s2 will not have overlapped keys with k1 or whatever inserted into m1 before ingest file s1 by the requirement of file ingestion (otherwise the m1 will be flushed first before any of the file ingestion completes). Therefore there in fact isn't any file reordering corruption.
- Single delete can decrease a file's largest seqno and ordering by `largest_seqno` can introduce a wrong ordering hence file reordering corruption
    - For example, consider the following sequence of events ("key@n" indicates key at seqno "n", Credit to ajkr  for this example)
        - an existing SST s1 contains only k1@1
        - insert k1@2 to memtable m1
        - ingest file s2 with k3@3, ingest file s3 with k4@4
        - insert single delete k5@5 in m1
        - flush m1 and result in new file s4 of seqno range [2, 5]
        - compact s1, s2, s3 and result in new file s5 of seqno range [1, 4]
        - compact s4 and result in new file s6 of seqno range [2] due to single delete
    - By the last step, we have file ordering by largest seqno (">" means "newer") : s5 > s6 while s6 contains a newer version of the k1's value (i.e, k1@2) than s5, which is a real reordering corruption. While this can be caught by `force_consistency_check=true`, there isn't a good way to prevent this from happening if ordering by `largest_seqno`

Therefore, we are redesigning the sorting criteria of L0 files and avoid above inconvenience. Credit to ajkr , we now introduce `epoch_num` which describes the order of a file being flushed or ingested/imported (compaction output file will has the minimum `epoch_num` among input files'). This will avoid the above inconvenience in the following ways:
- In the first case above, there will no longer be overlap seqno range check in `force_consistency_check=true` but `epoch_number`  ordering check. This will result in file ordering s1 <  s2 <  s4 (pre-compaction) and s3 < s4 (post-compaction) which won't trigger false positive corruption. See test class `DBCompactionTestL0FilesMisorderCorruption*` for more.
- In the second case above, this will result in file ordering s1 < s2 < s3 < s4 (pre-compacting s1, s2, s3), s5 < s4 (post-compacting s1, s2, s3), s5 < s6 (post-compacting s4), which are correct file ordering without causing any corruption.

**Summary:**
- Introduce `epoch_number` stored per `ColumnFamilyData` and sort CF's L0 files by their assigned `epoch_number` instead of `largest_seqno`.
  - `epoch_number` is increased and assigned upon `VersionEdit::AddFile()` for flush (or similarly for WriteLevel0TableForRecovery) and file ingestion (except for allow_behind_true, which will always get assigned as the `kReservedEpochNumberForFileIngestedBehind`)
  - Compaction output file  is assigned with the minimum `epoch_number` among input files'
      - Refit level: reuse refitted file's epoch_number
  -  Other paths needing `epoch_number` treatment:
     - Import column families: reuse file's epoch_number if exists. If not, assign one based on `NewestFirstBySeqNo`
     - Repair: reuse file's epoch_number if exists. If not, assign one based on `NewestFirstBySeqNo`.
  -  Assigning new epoch_number to a file and adding this file to LSM tree should be atomic. This is guaranteed by us assigning epoch_number right upon `VersionEdit::AddFile()` where this version edit will be apply to LSM tree shape right after by holding the db mutex (e.g, flush, file ingestion, import column family) or  by there is only 1 ongoing edit per CF (e.g, WriteLevel0TableForRecovery, Repair).
  - Assigning the minimum input epoch number to compaction output file won't misorder L0 files (even through later `Refit(target_level=0)`). It's due to for every key "k" in the input range, a legit compaction will cover a continuous epoch number range of that key. As long as we assign the key "k" the minimum input epoch number, it won't become newer or older than the versions of this key that aren't included in this compaction hence no misorder.
- Persist `epoch_number` of each file in manifest and recover `epoch_number` on db recovery
   - Backward compatibility with old db without `epoch_number` support is guaranteed by assigning `epoch_number` to recovered files by `NewestFirstBySeqno` order. See `VersionStorageInfo::RecoverEpochNumbers()` for more
   - Forward compatibility with manifest is guaranteed by flexibility of `NewFileCustomTag`
- Replace `force_consistent_check` on L0 with `epoch_number` and remove false positive check like case 1 with `largest_seqno` above
   - Due to backward compatibility issue, we might encounter files with missing epoch number at the beginning of db recovery. We will still use old L0 sorting mechanism (`NewestFirstBySeqno`) to check/sort them till we infer their epoch number. See usages of `EpochNumberRequirement`.
- Remove fix https://github.com/facebook/rocksdb/pull/5958#issue-511150930 and their outdated tests to file reordering corruption because such fix can be replaced by this PR.
- Misc:
   - update existing tests with `epoch_number` so make check will pass
   - update https://github.com/facebook/rocksdb/pull/5958#issue-511150930 tests to verify corruption is fixed using `epoch_number` and cover universal/fifo compaction/CompactRange/CompactFile cases
   - assert db_mutex is held for a few places before calling ColumnFamilyData::NewEpochNumber()

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10922

Test Plan:
- `make check`
- New unit tests under `db/db_compaction_test.cc`, `db/db_test2.cc`, `db/version_builder_test.cc`, `db/repair_test.cc`
- Updated tests (i.e, `DBCompactionTestL0FilesMisorderCorruption*`) under https://github.com/facebook/rocksdb/pull/5958#issue-511150930
- [Ongoing] Compatibility test: manually run 36a5686ec0 (with file ingestion off for running the `.orig` binary to prevent this bug affecting upgrade/downgrade formality checking) for 1 hour on `simple black/white box`, `cf_consistency/txn/enable_ts with whitebox + test_best_efforts_recovery with blackbox`
- [Ongoing] normal db stress test
- [Ongoing] db stress test with aggressive value https://github.com/facebook/rocksdb/pull/10761

Reviewed By: ajkr

Differential Revision: D41063187

Pulled By: hx235

fbshipit-source-id: 826cb23455de7beaabe2d16c57682a82733a32a9
2022-12-13 13:29:37 -08:00
Yanqin Jin
3d0d6b8140 Make best-efforts recovery verify SST unique ID before Version construction (#10962)
Summary:
The check for SST unique IDs added to best-efforts recovery (`Options::best_efforts_recovery` is true).

With best_efforts_recovery being true, RocksDB will recover to the latest point in
MANIFEST such that all valid SST files included up to this point pass unique ID checks as well.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10962

Test Plan: make check

Reviewed By: pdillinger

Differential Revision: D41378241

Pulled By: riversand963

fbshipit-source-id: a036064e2c17dec13d080a24ef2a9f85d607b16c
2022-11-22 22:53:31 -08:00
Gang Liao
deff48bcef Add blob source to retrieve blobs in RocksDB (#10198)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
In this task, we formally introduced the blob source to RocksDB.  BlobSource is a new abstraction layer that provides universal access to blobs, regardless of whether they are in the blob cache, secondary cache, or (remote) storage. Depending on user settings, it always fetch blobs from multi-tier cache and storage with minimal cost.

Note: The new `MultiGetBlob()` implementation is not included in the current PR. To go faster, we aim to create a separate PR for it in parallel!

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10198

Reviewed By: ltamasi

Differential Revision: D37294735

Pulled By: gangliao

fbshipit-source-id: 9cb50422d9dd1bc03798501c2778b6c7520c7a1e
2022-06-20 20:58:11 -07:00
Yanqin Jin
e0c84aa0dc Fix a race condition in WAL tracking causing DB open failure (#9715)
Summary:
There is a race condition if WAL tracking in the MANIFEST is enabled in a database that disables 2PC.

The race condition is between two background flush threads trying to install flush results to the MANIFEST.

Consider an example database with two column families: "default" (cfd0) and "cf1" (cfd1). Initially,
both column families have one mutable (active) memtable whose data backed by 6.log.

1. Trigger a manual flush for "cf1", creating a 7.log
2. Insert another key to "default", and trigger flush for "default", creating 8.log
3. BgFlushThread1 finishes writing 9.sst
4. BgFlushThread2 finishes writing 10.sst

```
Time  BgFlushThread1                                    BgFlushThread2
 |    mutex_.Lock()
 |    precompute min_wal_to_keep as 6
 |    mutex_.Unlock()
 |                                                     mutex_.Lock()
 |                                                     precompute min_wal_to_keep as 6
 |                                                     join MANIFEST write queue and mutex_.Unlock()
 |    write to MANIFEST
 |    mutex_.Lock()
 |    cfd1->log_number = 7
 |    Signal bg_flush_2 and mutex_.Unlock()
 |                                                     wake up and mutex_.Lock()
 |                                                     cfd0->log_number = 8
 |                                                     FindObsoleteFiles() with job_context->log_number == 7
 |                                                     mutex_.Unlock()
 |                                                     PurgeObsoleteFiles() deletes 6.log
 V
```

As shown in the above, BgFlushThread2 thinks that the min wal to keep is 6.log because "cf1" has unflushed data in 6.log (cf1.log_number=6).
Similarly, BgThread1 thinks that min wal to keep is also 6.log because "default" has unflushed data (default.log_number=6).
No WAL deletion will be written to MANIFEST because 6 is equal to `versions_->wals_.min_wal_number_to_keep`,
due to https://github.com/facebook/rocksdb/blob/7.1.fb/db/memtable_list.cc#L513:L514.
The bg flush thread that finishes last will perform file purging. `job_context.log_number` will be evaluated as 7, i.e.
the min wal that contains unflushed data, causing 6.log to be deleted. However, MANIFEST thinks 6.log should still exist.
If you close the db at this point, you won't be able to re-open it if `track_and_verify_wal_in_manifest` is true.

We must handle the case of multiple bg flush threads, and it is difficult for one bg flush thread to know
the correct min wal number until the other bg flush threads have finished committing to the manifest and updated
the `cfd::log_number`.
To fix this issue, we rename an existing variable `min_log_number_to_keep_2pc` to `min_log_number_to_keep`,
and use it to track WAL file deletion in non-2pc mode as well.
This variable is updated only 1) during recovery with mutex held, or 2) in the MANIFEST write thread.
`min_log_number_to_keep` means RocksDB will delete WALs below it, although there may be WALs
above it which are also obsolete. Formally, we will have [min_wal_to_keep, max_obsolete_wal]. During recovery, we
make sure that only WALs above max_obsolete_wal are checked and added back to `alive_log_files_`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9715

Test Plan:
```
make check
```
Also ran stress test below (with asan) to make sure it completes successfully.
```
TEST_TMPDIR=/dev/shm/rocksdb OPT=-g ASAN_OPTIONS=disable_coredump=0 \
CRASH_TEST_EXT_ARGS=--compression_type=zstd SKIP_FORMAT_BUCK_CHECKS=1 \
make J=52 -j52 blackbox_asan_crash_test
```

Reviewed By: ltamasi

Differential Revision: D34984412

Pulled By: riversand963

fbshipit-source-id: c7b21a8d84751bb55ea79c9f387103d21b231005
2022-03-23 19:41:31 -07:00
Levi Tamasi
42e0751b3a Clean up VersionStorageInfo a bit (#9494)
Summary:
The patch does some cleanup in and around `VersionStorageInfo`:
* Renames the method `PrepareApply` to `PrepareAppend` in `Version`
to make it clear that it is to be called before appending the `Version` to
`VersionSet` (via `AppendVersion`), not before applying any `VersionEdit`s.
* Introduces a helper method `VersionStorageInfo::PrepareForVersionAppend`
(called by `Version::PrepareAppend`) that encapsulates the population of the
various derived data structures in `VersionStorageInfo`, and turns the
methods computing the derived structures (`UpdateNumNonEmptyLevels`,
`CalculateBaseBytes` etc.) into private helpers.
* Changes `Version::PrepareAppend` so it only calls `UpdateAccumulatedStats`
if the `update_stats` flag is set. (Earlier, this was checked by the callee.)
Related to this, it also moves the call to `ComputeCompensatedSizes` to
`VersionStorageInfo::PrepareForVersionAppend`.
* Updates and cleans up `version_builder_test`, `version_set_test`, and
`compaction_picker_test` so `PrepareForVersionAppend` is called anytime
a new `VersionStorageInfo` is set up or saved. This cleanup also involves
splitting `VersionStorageInfoTest.MaxBytesForLevelDynamic`
into multiple smaller test cases.
* Fixes up a bunch of comments that were outdated or just plain incorrect.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9494

Test Plan: Ran `make check` and the crash test script for a while.

Reviewed By: riversand963

Differential Revision: D33971666

Pulled By: ltamasi

fbshipit-source-id: fda52faac7783041126e4f8dec0fe01bdcadf65a
2022-02-04 08:19:20 -08:00
Peter Dillinger
fc9d4071f0 Fast path for detecting unchanged prefix_extractor (#9407)
Summary:
Fixes a major performance regression in 6.26, where
extra CPU is spent in SliceTransform::AsString when reads involve
a prefix_extractor (Get, MultiGet, Seek). Common case performance
is now better than 6.25.

This change creates a "fast path" for verifying that the current prefix
extractor is unchanged and compatible with what was used to
generate a table file. This fast path detects the common case by
pointer comparison on the current prefix_extractor and a "known
good" prefix extractor (if applicable) that is saved at the time the
table reader is opened. The "known good" prefix extractor is saved
as another shared_ptr copy (in an existing field, however) to ensure
the pointer is not recycled.

When the prefix_extractor has changed to a different instance but
same compatible configuration (rare, odd), performance is still a
regression compared to 6.25, but this is likely acceptable because
of the oddity of such a case. The performance of incompatible
prefix_extractor is essentially unchanged.

Also fixed a minor case (ForwardIterator) where a prefix_extractor
could be used via a raw pointer after being freed as a shared_ptr,
if replaced via SetOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9407

Test Plan:
## Performance
Populate DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Running head-to-head comparisons simultaneously with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=seekrandom -num=10000000 -duration=20 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Below each is compared by ops/sec vs. baseline which is version 6.25 (multiple baseline runs because of variable machine load)

v6.26: 4833 vs. 6698 (<- major regression!)
v6.27: 4737 vs. 6397 (still)
New: 6704 vs. 6461 (better than baseline in common case)
Disabled fastpath: 4843 vs. 6389 (e.g. if prefix extractor instance changes but is still compatible)
Changed prefix size (no usable filter) in new: 787 vs. 5927
Changed prefix size (no usable filter) in new & baseline: 773 vs. 784

Reviewed By: mrambacher

Differential Revision: D33677812

Pulled By: pdillinger

fbshipit-source-id: 571d9711c461fb97f957378a061b7e7dbc4d6a76
2022-01-21 11:37:46 -08:00
jsteemann
255aefb628 Add filename to several Corruption messages (#9239)
Summary:
This change adds the filename of the offending filen to several place that produce Status objects with code `kCorruption`.
This is not an attempt to have every Corruption message in the codebase extended with the filename, but it is a start.
The motivation for the change was to quickly diagnose which file is corrupted when a large database is openend and there is not option to copy it offsite for analysis, run strace or install the ldb tool.
In the particular case in question, the error message improved from a mere
```
Corruption: checksum mismatch
```
to
```
Corruption: checksum mismatch in file /path/to/db/engine-rocksdb/MANIFEST-000171
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9239

Reviewed By: jay-zhuang

Differential Revision: D33237742

Pulled By: riversand963

fbshipit-source-id: bd42559cfbf786a0a674d091671d1a2bf07bdd31
2022-01-07 18:09:48 -08:00
Andrew Kryczka
b860a42158 Recover to exact latest seqno of data committed to MANIFEST (#9305)
Summary:
The LastSequence field in the MANIFEST file is the baseline seqno for a recovered DB. Recovering WAL entries might cause the recovered DB's seqno to advance above this baseline, but the recovered DB will never use a smaller seqno.

Before this PR, we were writing the DB's seqno at the time of LogAndApply() as the LastSequence value. This works in the sense that it is a large enough baseline for the recovered DB that it'll never overwrite any records in existing SST files. At the same time, it's arbitrarily larger than what's needed. This behavior comes from LevelDB, where there was no tracking of largest seqno in an SST file.

Now we know the largest seqno of newly written SST files, so we can write an exact value in LastSequence that actually reflects the largest seqno in any file referred to by the MANIFEST. This is primarily useful for correctness testing with unsynced data loss, where the recovered DB's seqno needs to indicate what records were recovered.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9305

Test Plan:
- https://github.com/facebook/rocksdb/issues/9338 adds crash-recovery correctness testing coverage for WAL disabled use cases
- https://github.com/facebook/rocksdb/issues/9357 will extend that testing to cover file ingestion
- Added assertion at end of LogAndApply() for `VersionSet::descriptor_last_sequence_` consistency with files
- Manually tested upgrade/downgrade compatibility with a custom crash test that randomly picks between a `db_stress` built with and without this PR (for old code it must run with `-disable_wal=0`)

Reviewed By: riversand963

Differential Revision: D33182770

Pulled By: ajkr

fbshipit-source-id: 0bfafaf685f347cc8cb0e1d62e0186340a738f7d
2022-01-05 16:02:21 -08:00
Yanqin Jin
43ac7a2774 Fix an assertion failure when ManifestTailer switches to new Manifest in multi-cf mode (#9143)
Summary:
Original unit test fail to test the case of multi-cf mode switching to new manifest. The assertion
failure will trigger when the primary instance reopens and secondary continues to tail the
newly-created MANIFEST. Fix the assertion failure and update existing unit tests.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9143

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D32574233

Pulled By: riversand963

fbshipit-source-id: 857ddbe994019091276458abebcf8e2b65340468
2021-11-19 19:53:40 -08:00
Peter Dillinger
230660be73 Improve / clean up meta block code & integrity (#9163)
Summary:
* Checksums are now checked on meta blocks unless specifically
suppressed or not applicable (e.g. plain table). (Was other way around.)
This means a number of cases that were not checking checksums now are,
including direct read TableProperties in Version::GetTableProperties
(fixed in meta_blocks ReadTableProperties), reading any block from
PersistentCache (fixed in BlockFetcher), read TableProperties in
SstFileDumper (ldb/sst_dump/BackupEngine) before table reader open,
maybe more.
* For that to work, I moved the global_seqno+TableProperties checksum
logic to the shared table/ code, because that is used by many utilies
such as SstFileDumper.
* Also for that to work, we have to know when we're dealing with a block
that has a checksum (trailer), so added that capability to Footer based
on magic number, and from there BlockFetcher.
* Knowledge of trailer presence has also fixed a problem where other
table formats were reading blocks including bytes for a non-existant
trailer--and awkwardly kind-of not using them, e.g. no shared code
checking checksums. (BlockFetcher compression type was populated
incorrectly.) Now we only read what is needed.
* Minimized code duplication and differing/incompatible/awkward
abstractions in meta_blocks.{cc,h} (e.g. SeekTo in metaindex block
without parsing block handle)
* Moved some meta block handling code from table_properties*.*
* Moved some code specific to block-based table from shared table/ code
to BlockBasedTable class. The checksum stuff means we can't completely
separate it, but things that don't need to be in shared table/ code
should not be.
* Use unique_ptr rather than raw ptr in more places. (Note: you can
std::move from unique_ptr to shared_ptr.)

Without enhancements to GetPropertiesOfAllTablesTest (see below),
net reduction of roughly 100 lines of code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9163

Test Plan:
existing tests and
* Enhanced DBTablePropertiesTest.GetPropertiesOfAllTablesTest to verify that
checksums are now checked on direct read of table properties by TableCache
(new test would fail before this change)
* Also enhanced DBTablePropertiesTest.GetPropertiesOfAllTablesTest to test
putting table properties under old meta name
* Also generally enhanced that same test to actually test what it was
supposed to be testing already, by kicking things out of table cache when
we don't want them there.

Reviewed By: ajkr, mrambacher

Differential Revision: D32514757

Pulled By: pdillinger

fbshipit-source-id: 507964b9311d186ae8d1131182290cbd97a99fa9
2021-11-18 11:43:44 -08:00
mrambacher
13ae16c315 Cleanup includes in dbformat.h (#8930)
Summary:
This header file was including everything and the kitchen sink when it did not need to.  This resulted in many places including this header when they needed other pieces instead.

Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.

Hopefully, this sort of code hygiene cleanup will speed up the builds...

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930

Reviewed By: pdillinger

Differential Revision: D31142788

Pulled By: mrambacher

fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
2021-09-29 04:04:40 -07:00
Yanqin Jin
f235f4b0a3 Fix a bug of secondary instance sequence going backward (#8653)
Summary:
Recent refactor of `ReactiveVersionSet::ReadAndApply()` uses
`ManifestTailer` whose `Iterate()` method can cause the db's
`last_sequence_` to go backward. Consequently, read requests can see
out-dated data. For example, latest changes to the primary will not be
seen on the secondary even after a `TryCatchUpWithPrimary()` if no new
write batches are read from the WALs and no new MANIFEST entries are
read from the MANIFEST.

Fix the bug so that `VersionEditHandler::CheckIterationResult` will
never decrease `last_sequence_`, `last_allocated_sequence_` and
`last_published_sequence_`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8653

Test Plan: make check

Reviewed By: jay-zhuang

Differential Revision: D30272084

Pulled By: riversand963

fbshipit-source-id: c6a49c534b2509b93ef62d8936ed0acd5b860eaa
2021-08-24 18:18:36 -07:00
Baptiste Lemaire
c521a9ab2b Retire superfluous functions introduced in earlier mempurge PRs. (#8558)
Summary:
The main challenge to make the memtable garbage collection prototype (nicknamed `mempurge`) was to not get rid of WAL files that contain unflushed (but mempurged) data. That was successfully guaranteed by not writing the VersionEdit to the MANIFEST file after a successful mempurge.
By not writing VersionEdits to the `MANIFEST` file after a succesful mempurge operation, we do not change the earliest log file number that contains unflushed data: `cfd->GetLogNumber()` (`cfd->SetLogNumber()` is only called in `VersionSet::ProcessManifestWrites`). As a result, a number of functions introduced earlier just for the mempurge operation are not obscolete/redundant. (e.g.: `FlushJob::ExtractEarliestLogFileNumber`), and this PR aims at cleaning up all these now-unnecessary functions. In particular, we no longer need to store the earliest log file number in the `MemTable` struct itself. This PR therefore also reverts the `MemTable` struct to its original form.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8558

Test Plan: Already included in `db_flush_test.cc`.

Reviewed By: anand1976

Differential Revision: D29764351

Pulled By: bjlemaire

fbshipit-source-id: 0f43b260fa270251862512f397d3f24ee62e8437
2021-07-22 18:29:13 -07:00
Baptiste Lemaire
206845c057 Mempurge support for wal (#8528)
Summary:
In this PR, `mempurge` is made compatible with the Write Ahead Log: in case of recovery, the DB is now capable of recovering the data that was "mempurged" and kept in the `imm()` list of immutable memtables.
The twist was to add a uint64_t to the `memtable` struct to store the number of the earliest log file containing entries from the `memtable`. When a `Flush` operation is replaced with a `MemPurge`, the `VersionEdit` (which usually contains the new min log file number to pick up for recovery and the level 0 file path of the newly created SST file) is no longer appended to the manifest log, and every time the `deleteWal` method is called, a check is made on the list of immutable memtables.
This PR also includes a unit test that verifies that no data is lost upon Reopening of the database when the mempurge feature is activated. This extensive unit test includes two column families, with valid data contained in the imm() at time of "crash"/reopening (recovery).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8528

Reviewed By: pdillinger

Differential Revision: D29701097

Pulled By: bjlemaire

fbshipit-source-id: 072a900fb6ccc1edcf5eef6caf88f3060238edf9
2021-07-15 17:49:13 -07:00
Baptiste Lemaire
d61a449364 Fixed manifest_dump issues when printing keys and values containing null characters (#8378)
Summary:
Changed fprintf function to fputc in ApplyVersionEdit, and replaced null characters with whitespaces.
Added unit test in ldb_test.py - verifies that manifest_dump --verbose output is correct when keys and values containing null characters are inserted.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8378

Reviewed By: pdillinger

Differential Revision: D29034584

Pulled By: bjlemaire

fbshipit-source-id: 50833687a8a5f726e247c38457eadc3e6dbab862
2021-06-10 12:55:20 -07:00
Yanqin Jin
314352761f Ignore comparator name mismatch in ldb manifest dump (#8216)
Summary:
RocksDB allows user-specified custom comparators which may not be known to `ldb`,
a built-in tool for checking/mutating the database. Therefore, column family comparator
names mismatch encountered during manifest dump should not prevent the dumping from
proceeding.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8216

Test Plan:
```
make check
```

Also manually do the following
```
KEEP_DB=1 ./db_with_timestamp_basic_test
./ldb --db=<db> manifest_dump --verbose
```
The ldb should succeed and print something like:
```
...
--------------- Column family "default"  (ID 0) --------------
log number: 6
comparator: <TestComparator>, but the comparator object is not available.
...
```

Reviewed By: ltamasi

Differential Revision: D27927581

Pulled By: riversand963

fbshipit-source-id: f610b2c842187d17f575362070209ee6b74ec6d4
2021-04-21 20:43:10 -07:00
Yanqin Jin
b0e20194ea Handle blob files when options.best_efforts_recovery is true (#8180)
Summary:
If `options.best_efforts_recovery == true`, RocksDB currently tolerates missing table files and recovers to the latest version without missing table files (not considering WAL). It is necessary to handle blob files as well to make the feature more complete.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8180

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D27840556

Pulled By: riversand963

fbshipit-source-id: 041685d0dc2e7779ac4f0374c07a8a327704aa5e
2021-04-19 11:56:14 -07:00
Yanqin Jin
64517d184a Make secondary instance use ManifestTailer (#7998)
Summary:
This PR

- adds a class `ManifestTailer` that inherits from `VersionEditHandlerPointInTime`. `ManifestTailer::Iterate()` can be called multiple times to tail the primary instance's MANIFEST and apply the changes to the secondary,
- updates the implementation of `ReactiveVersionSet::ReadAndApply` to use this class,
- removes unused code in version_set.cc,
- updates existing tests, e.g. removing deleted sync points from unit tests,
- adds a new test to address the bug in https://github.com/facebook/rocksdb/issues/7815.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7998

Test Plan:
make check
Existing and newly-added tests in version_set_test.cc and db_secondary_test.cc

Reviewed By: jay-zhuang

Differential Revision: D26926641

Pulled By: riversand963

fbshipit-source-id: 8d4dd15db0ba863c213f743e33b5a207e948c980
2021-03-10 10:59:44 -08:00
Akanksha Mahajan
f19612970d Support retrieving checksums for blob files from the MANIFEST when checkpointing (#8003)
Summary:
The checkpointing logic supports passing file level checksums
to the copy_file_cb callback function which is used by the backup code
for detecting corruption during file copies.
However, this is currently implemented only for table files.

This PR extends the checksum retrieval to blob files as well.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8003

Test Plan: Add new test units

Reviewed By: ltamasi

Differential Revision: D26680701

Pulled By: akankshamahajan15

fbshipit-source-id: 1bd1e2464df6e9aa31091d35b8c72786d94cd1c5
2021-03-01 20:07:07 -08:00
mrambacher
cc2a180d00 Add more tests to the ASC pass list (#7834)
Summary:
Fixed the following  to now pass ASC checks:
* `ttl_test`
* `blob_db_test`
* `backupable_db_test`,
* `delete_scheduler_test`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7834

Reviewed By: jay-zhuang

Differential Revision: D25795398

Pulled By: ajkr

fbshipit-source-id: a10037817deda4fc7cbb353a2e00b62ed89b6476
2021-01-07 15:22:53 -08:00