database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-27 12:41:57 +03:00
Code Activity

Track invalidation_reason in pg_replication_slots.

Browse Source 
Till now, the reason for replication slot invalidation is not tracked
directly in pg_replication_slots. A recent commit 007693f2a3 added
'conflict_reason' to show the reasons for slot conflict/invalidation, but
only for logical slots.

This commit adds a new column 'invalidation_reason' to show invalidation
reasons for both physical and logical slots. And, this commit also turns
'conflict_reason' text column to 'conflicting' boolean column (effectively
reverting commit 007693f2a3). The 'conflicting' column is true for
invalidation reasons 'rows_removed' and 'wal_level_insufficient' because
those make the slot conflict with recovery. When 'conflicting' is true,
one can now look at the new 'invalidation_reason' column for the reason
for the logical slot's conflict with recovery.

The new 'invalidation_reason' column will also be useful to track other
invalidation reasons in the future commit.

Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Amit Kapila, Shveta Malik
Discussion: https://www.postgresql.org/message-id/ZfR7HuzFEswakt/a%40ip-10-97-1-34.eu-west-3.compute.internal
Discussion: https://www.postgresql.org/message-id/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com
This commit is contained in:
Amit Kapila
2024-03-22 13:52:05 +05:30
parent b4080fa3dc
commit 6ae701b437
13 changed files with 94 additions and 72 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/backend/replication/logical/slotsync.c
View File

@ -663,7 +663,7 @@ synchronize_slots(WalReceiverConn *wrconn)
bool started_tx = false;
const char *query = "SELECT slot_name, plugin, confirmed_flush_lsn,"
" restart_lsn, catalog_xmin, two_phase, failover,"
" database, conflict_reason"
" database, invalidation_reason"
" FROM pg_catalog.pg_replication_slots"
" WHERE failover and NOT temporary";

49
src/backend/replication/slot.c
View File

@ -1525,14 +1525,14 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
XLogRecPtr initial_effective_xmin = InvalidXLogRecPtr;
XLogRecPtr initial_catalog_effective_xmin = InvalidXLogRecPtr;
XLogRecPtr initial_restart_lsn = InvalidXLogRecPtr;
ReplicationSlotInvalidationCause conflict_prev PG_USED_FOR_ASSERTS_ONLY = RS_INVAL_NONE;
ReplicationSlotInvalidationCause invalidation_cause_prev PG_USED_FOR_ASSERTS_ONLY = RS_INVAL_NONE;
for (;;)
{
XLogRecPtr restart_lsn;
NameData slotname;
int active_pid = 0;
ReplicationSlotInvalidationCause conflict = RS_INVAL_NONE;
ReplicationSlotInvalidationCause invalidation_cause = RS_INVAL_NONE;
Assert(LWLockHeldByMeInMode(ReplicationSlotControlLock, LW_SHARED));
@ -1554,17 +1554,14 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
restart_lsn = s->data.restart_lsn;
/*
* If the slot is already invalid or is a non conflicting slot, we
* don't need to do anything.
*/
/* we do nothing if the slot is already invalid */
if (s->data.invalidated == RS_INVAL_NONE)
{
/*
* The slot's mutex will be released soon, and it is possible that
* those values change since the process holding the slot has been
* terminated (if any), so record them here to ensure that we
* would report the correct conflict cause.
* would report the correct invalidation cause.
*/
if (!terminated)
{
@ -1578,7 +1575,7 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
case RS_INVAL_WAL_REMOVED:
if (initial_restart_lsn != InvalidXLogRecPtr &&
initial_restart_lsn < oldestLSN)
conflict = cause;
invalidation_cause = cause;
break;
case RS_INVAL_HORIZON:
if (!SlotIsLogical(s))
@ -1589,15 +1586,15 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
if (TransactionIdIsValid(initial_effective_xmin) &&
TransactionIdPrecedesOrEquals(initial_effective_xmin,
snapshotConflictHorizon))
conflict = cause;
invalidation_cause = cause;
else if (TransactionIdIsValid(initial_catalog_effective_xmin) &&
TransactionIdPrecedesOrEquals(initial_catalog_effective_xmin,
snapshotConflictHorizon))
conflict = cause;
invalidation_cause = cause;
break;
case RS_INVAL_WAL_LEVEL:
if (SlotIsLogical(s))
conflict = cause;
invalidation_cause = cause;
break;
case RS_INVAL_NONE:
pg_unreachable();
@ -1605,14 +1602,14 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
}
/*
* The conflict cause recorded previously should not change while the
* process owning the slot (if any) has been terminated.
* The invalidation cause recorded previously should not change while
* the process owning the slot (if any) has been terminated.
*/
Assert(!(conflict_prev != RS_INVAL_NONE && terminated &&
conflict_prev != conflict));
Assert(!(invalidation_cause_prev != RS_INVAL_NONE && terminated &&
invalidation_cause_prev != invalidation_cause));
/* if there's no conflict, we're done */
if (conflict == RS_INVAL_NONE)
/* if there's no invalidation, we're done */
if (invalidation_cause == RS_INVAL_NONE)
{
SpinLockRelease(&s->mutex);
if (released_lock)
@ -1632,13 +1629,13 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
{
MyReplicationSlot = s;
s->active_pid = MyProcPid;
s->data.invalidated = conflict;
s->data.invalidated = invalidation_cause;
/*
* XXX: We should consider not overwriting restart_lsn and instead
* just rely on .invalidated.
*/
if (conflict == RS_INVAL_WAL_REMOVED)
if (invalidation_cause == RS_INVAL_WAL_REMOVED)
s->data.restart_lsn = InvalidXLogRecPtr;
/* Let caller know */
@ -1681,7 +1678,7 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
*/
if (last_signaled_pid != active_pid)
{
ReportSlotInvalidation(conflict, true, active_pid,
ReportSlotInvalidation(invalidation_cause, true, active_pid,
slotname, restart_lsn,
oldestLSN, snapshotConflictHorizon);
@ -1694,7 +1691,7 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
last_signaled_pid = active_pid;
terminated = true;
conflict_prev = conflict;
invalidation_cause_prev = invalidation_cause;
}
/* Wait until the slot is released. */
@ -1727,7 +1724,7 @@ InvalidatePossiblyObsoleteSlot(ReplicationSlotInvalidationCause cause,
ReplicationSlotSave();
ReplicationSlotRelease();
ReportSlotInvalidation(conflict, false, active_pid,
ReportSlotInvalidation(invalidation_cause, false, active_pid,
slotname, restart_lsn,
oldestLSN, snapshotConflictHorizon);
@ -2356,21 +2353,21 @@ RestoreSlotFromDisk(const char *name)
}
/*
* Maps a conflict reason for a replication slot to
* Maps an invalidation reason for a replication slot to
* ReplicationSlotInvalidationCause.
*/
ReplicationSlotInvalidationCause
GetSlotInvalidationCause(const char *conflict_reason)
GetSlotInvalidationCause(const char *invalidation_reason)
{
ReplicationSlotInvalidationCause cause;
ReplicationSlotInvalidationCause result = RS_INVAL_NONE;
bool found PG_USED_FOR_ASSERTS_ONLY = false;
Assert(conflict_reason);
Assert(invalidation_reason);
for (cause = RS_INVAL_NONE; cause <= RS_INVAL_MAX_CAUSES; cause++)
{
if (strcmp(SlotInvalidationCauses[cause], conflict_reason) == 0)
if (strcmp(SlotInvalidationCauses[cause], invalidation_reason) == 0)
{
found = true;
result = cause;

25
src/backend/replication/slotfuncs.c
View File

@ -239,7 +239,7 @@ pg_drop_replication_slot(PG_FUNCTION_ARGS)
Datum
pg_get_replication_slots(PG_FUNCTION_ARGS)
{
#define PG_GET_REPLICATION_SLOTS_COLS 17
#define PG_GET_REPLICATION_SLOTS_COLS 18
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
XLogRecPtr currlsn;
int slotno;
@ -263,6 +263,7 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
bool nulls[PG_GET_REPLICATION_SLOTS_COLS];
WALAvailability walstate;
int i;
ReplicationSlotInvalidationCause cause;
if (!slot->in_use)
continue;
@ -409,18 +410,28 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
values[i++] = BoolGetDatum(slot_contents.data.two_phase);
if (slot_contents.data.database == InvalidOid)
cause = slot_contents.data.invalidated;
if (SlotIsPhysical(&slot_contents))
nulls[i++] = true;
else
{
ReplicationSlotInvalidationCause cause = slot_contents.data.invalidated;
if (cause == RS_INVAL_NONE)
nulls[i++] = true;
/*
* rows_removed and wal_level_insufficient are the only two
* reasons for the logical slot's conflict with recovery.
*/
if (cause == RS_INVAL_HORIZON ||
cause == RS_INVAL_WAL_LEVEL)
values[i++] = BoolGetDatum(true);
else
values[i++] = CStringGetTextDatum(SlotInvalidationCauses[cause]);
values[i++] = BoolGetDatum(false);
}
if (cause == RS_INVAL_NONE)
nulls[i++] = true;
else
values[i++] = CStringGetTextDatum(SlotInvalidationCauses[cause]);
values[i++] = BoolGetDatum(slot_contents.data.failover);
values[i++] = BoolGetDatum(slot_contents.data.synced);