Before commit 6112853cda in MySQL 4.1.1
introduced the parameter innodb_file_per_table, all InnoDB data was
written to the InnoDB system tablespace (often named ibdata1).
A serious design problem is that once the system tablespace has grown to
some size, it cannot shrink even if the data inside it has been deleted.
There are also other design problems, such as the server hang MDEV-29930
that should only be possible when using innodb_file_per_table=0 and
innodb_undo_tablespaces=0 (storing both tables and undo logs in the
InnoDB system tablespace).
The parameter innodb_change_buffering was deprecated
in commit b5852ffbee.
Starting with commit baf276e6d4
(MDEV-19229) the number of innodb_undo_tablespaces can be increased,
so that the undo logs can be moved out of the system tablespace
of an existing installation.
If all these things (tables, undo logs, and the change buffer) are
removed from the InnoDB system tablespace, the only variable-size
data structure inside it is the InnoDB data dictionary.
DDL operations on .ibd files was optimized in
commit 86dc7b4d4c (MDEV-24626).
That should have removed any thinkable performance advantage of
using innodb_file_per_table=0.
Since there should be no benefit of setting innodb_file_per_table=0,
the parameter should be deprecated. Starting with MySQL 5.6 and
MariaDB Server 10.0, the default value is innodb_file_per_table=1.
The log overwrite warnings are not being reliably emitted in all
debug-instrumented environments. It may be related to the
scheduling of some InnoDB internal activity, such as the purging
of committed transaction history.
The InnoDB write-ahead log ib_logfile0 is of fixed size,
specified by innodb_log_file_size. If the tail of the log
manages to overwrite the head (latest checkpoint) of the log,
crash recovery will be broken.
Let us clarify the messages about this, including adding
a message on the completion of a log checkpoint that notes
that the dangerous situation is over.
To reproduce the dangerous scenario, we will introduce the
debug injection label ib_log_checkpoint_avoid_hard, which will
avoid log checkpoints even harder than the previous
ib_log_checkpoint_avoid.
log_t::overwrite_warned: The first known dangerous log sequence number.
Set in log_close() and cleared in log_write_checkpoint_info(),
which will output a "Crash recovery was broken" message.
As main() invokes parse_page() when -S or -D are set, it can be a case
when parse_page() is invoked when -D filename is not set, that is why
any attempt to write to page dump file must be done only if the file
name is set with -D.
The bug is caused by 2ef7a5a13a
(MDEV-13443).
A few regression tests invoke heavy flushing of the buffer pool
and may trigger warnings that tablespaces could not be deleted
because of pending writes. Those warnings are to be expected
during the execution of such tests.
The warnings are also frequently seen with Valgrind or MemorySanitizer.
For those, the global suppression in have_innodb.inc does the trick.
Shutdown of mtr tests may be too impatient, esp on CI environment where
10 seconds of `arg` of `shutdown_server arg` may not be enough for the clean
shutdown to complete.
This is fixed to remove explicit non-zero timeout argument to
`shutdown_server` from all mtr tests. mysqltest computes 60 seconds default
value for the timeout for the argless `shutdown_server` command.
This policy is additionally ensured with a compile time assert.
Added the condition in innochecksum tool to check page id mismatch.
This could catch the write corruption caused by InnoDB.
Added the debug insert inside fil_io() to check whether it writes
the page to wrong offset.
MariaDB data-at-rest encryption (innodb_encrypt_tables)
had repurposed the same unused data field that was repurposed
in MySQL 5.7 (and MariaDB 10.2) for the Split Sequence Number (SSN)
field of SPATIAL INDEX. Because of this, MariaDB was unable to
support encryption on SPATIAL INDEX pages.
Furthermore, InnoDB page checksums skipped some bytes, and there
are multiple variations and checksum algorithms. By default,
InnoDB accepts all variations of all algorithms that ever existed.
This unnecessarily weakens the page checksums.
We hereby introduce two more innodb_checksum_algorithm variants
(full_crc32, strict_full_crc32) that are special in a way:
When either setting is active, newly created data files will
carry a flag (fil_space_t::full_crc32()) that indicates that
all pages of the file will use a full CRC-32C checksum over the
entire page contents (excluding the bytes where the checksum
is stored, at the very end of the page). Such files will always
use that checksum, no matter what the parameter
innodb_checksum_algorithm is assigned to.
For old files, the old checksum algorithms will continue to be
used. The value strict_full_crc32 will be equivalent to strict_crc32
and the value full_crc32 will be equivalent to crc32.
ROW_FORMAT=COMPRESSED tables will only use the old format.
These tables do not support new features, such as larger
innodb_page_size or instant ADD/DROP COLUMN. They may be
deprecated in the future. We do not want an unnecessary
file format change for them.
The new full_crc32() format also cleans up the MariaDB tablespace
flags. We will reserve flags to store the page_compressed
compression algorithm, and to store the compressed payload length,
so that checksum can be computed over the compressed (and
possibly encrypted) stream and can be validated without
decrypting or decompressing the page.
In the full_crc32 format, there no longer are separate before-encryption
and after-encryption checksums for pages. The single checksum is
computed on the page contents that is written to the file.
We do not make the new algorithm the default for two reasons.
First, MariaDB 10.4.2 was a beta release, and the default values
of parameters should not change after beta. Second, we did not
yet implement the full_crc32 format for page_compressed pages.
This will be fixed in MDEV-18644.
This is joint work with Marko Mäkelä.
Always read full page 0 to determine does tablespace contain
encryption metadata. Tablespaces that are page compressed or
page compressed and encrypted do not compare checksum as
it does not exists. For encrypted tables use checksum
verification written for encrypted tables and normal tables
use normal method.
buf_page_is_checksum_valid_crc32
buf_page_is_checksum_valid_innodb
buf_page_is_checksum_valid_none
Modify Innochecksum logging to file to avoid compilation
warnings.
fil0crypt.cc fil0crypt.h
Modify to be able to use in innochecksum compilation and
move fil_space_verify_crypt_checksum to end of the file.
Add innochecksum logging to file.
univ.i
Add innochecksum strict_verify, log_file and cur_page_num
variables as extern.
page_zip_verify_checksum
Add innochecksum logging to file and remove unnecessary code.
innochecksum.cc
Lot of changes most notable able to read encryption
metadata from page 0 of the tablespace.
Added test case where we corrupt intentionally
FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION (encryption key version)
FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION+4 (post encryption checksum)
FIL_DATA+10 (data)
This is basically port of WL6045:Improve Innochecksum with some
code refactoring on innochecksum.
Added page0size.h include from 10.2 to make 10.1 vrs 10.2 innochecksum
as identical as possible.
Added page 0 checksum checking and if that fails whole test fails.
Always read full page 0 to determine does tablespace contain
encryption metadata. Tablespaces that are page compressed or
page compressed and encrypted do not compare checksum as
it does not exists. For encrypted tables use checksum
verification written for encrypted tables and normal tables
use normal method.
buf_page_is_checksum_valid_crc32
buf_page_is_checksum_valid_innodb
buf_page_is_checksum_valid_none
Add Innochecksum logging to file
buf_page_is_corrupted
Remove ib_logf and page_warn_strict_checksum
calls in innochecksum compilation. Add innochecksum
logging to file.
fil0crypt.cc fil0crypt.h
Modify to be able to use in innochecksum compilation and
move fil_space_verify_crypt_checksum to end of the file.
Add innochecksum logging to file.
univ.i
Add innochecksum strict_verify, log_file and cur_page_num
variables as extern.
page_zip_verify_checksum
Add innochecksum logging to file.
innochecksum.cc
Lot of changes most notable able to read encryption
metadata from page 0 of the tablespace.
Added test case where we corrupt intentionally
FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION (encryption key version)
FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION+4 (post encryption checksum)
FIL_DATA+10 (data)
The issue was a bad merge of MDEV-12253 from 10.1 to 10.2
in commit f9cc391863.
In that merge, I wrongly assumed that all test file conflicts
for mysql-test/suite/encryption had been properly resolved in
bb-10.2-MDEV-12253 (commit 76aa6be77635c7017459ce33b41c837c9acb606d)
while in fact, some files there had been copied from the 10.1 branch.
This commit is based on a manually done conflict resolution of
the mysql-test/suite/encryption on the same merge, applied to
the current 10.2 branch.
As part of this commit, the test encryption.innodb-bad-key-change4
which was shortly disabled due to MDEV-11336 will be re-enabled again.
(While the test enables innodb_defragment, it does not fail even though
enabling innodb_defragment currently has no effect.)
