diff options
| -rw-r--r-- | src/backend/storage/ipc/procarray.c | 5 | ||||
| -rw-r--r-- | src/backend/storage/ipc/standby.c | 8 |
2 files changed, 11 insertions, 2 deletions
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index d38164caa73..8c0d7b0ea95 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -1564,6 +1564,11 @@ ProcArrayInstallImportedXmin(TransactionId xmin, TransactionId sourcexid) * We don't worry about updating other counters, we want to keep this as * simple as possible and leave GetSnapshotData() as the primary code for * that bookkeeping. + * + * Note that if any transaction has overflowed its cached subtransactions + * then there is no real need include any subtransactions. That isn't a + * common enough case to worry about optimising the size of the WAL record, + * and we may wish to see that data for diagnostic purposes anyway. */ RunningTransactions GetRunningTransactionData(void) diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c index 43f74112733..905d33148a9 100644 --- a/src/backend/storage/ipc/standby.c +++ b/src/backend/storage/ipc/standby.c @@ -540,6 +540,10 @@ StandbyTimeoutHandler(void) * RelationLockList, so we can keep track of the various entries made by * the Startup process's virtual xid in the shared lock table. * + * We record the lock against the top-level xid, rather than individual + * subtransaction xids. This means AccessExclusiveLocks held by aborted + * subtransactions are not released as early as possible on standbys. + * * List elements use type xl_rel_lock, since the WAL record type exactly * matches the information that we need to keep track of. * @@ -673,8 +677,8 @@ StandbyReleaseAllLocks(void) /* * StandbyReleaseOldLocks - * Release standby locks held by XIDs that aren't running, as long - * as they're not prepared transactions. + * Release standby locks held by top-level XIDs that aren't running, + * as long as they're not prepared transactions. */ void StandbyReleaseOldLocks(int nxids, TransactionId *xids) |