diff options
Diffstat (limited to 'src/backend/access/transam/xact.c')
| -rw-r--r-- | src/backend/access/transam/xact.c | 54 |
1 files changed, 32 insertions, 22 deletions
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index d32a6dda978..f35e8d9203e 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.107 2001/07/15 22:48:16 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.108 2001/07/16 22:43:33 tgl Exp $ * * NOTES * Transaction aborts can now occur two ways: @@ -1018,16 +1018,21 @@ CommitTransaction(void) CloseSequences(); AtEOXact_portals(); + + /* Here is where we really truly commit. */ RecordTransactionCommit(); /* * Let others know about no transaction in progress by me. Note that - * this must be done _before_ releasing locks we hold and + * this must be done _before_ releasing locks we hold and _after_ + * RecordTransactionCommit. + * * SpinAcquire(SInvalLock) is required: UPDATE with xid 0 is blocked * by xid 1' UPDATE, xid 1 is doing commit while xid 2 gets snapshot - * if xid 2' GetSnapshotData sees xid 1 as running then it must see * xid 0 as running as well or it will see two tuple versions - one - * deleted by xid 1 and one inserted by xid 0. + * deleted by xid 1 and one inserted by xid 0. See notes in + * GetSnapshotData. */ if (MyProc != (PROC *) NULL) { @@ -1038,6 +1043,12 @@ CommitTransaction(void) SpinRelease(SInvalLock); } + /* + * This is all post-commit cleanup. Note that if an error is raised + * here, it's too late to abort the transaction. This should be just + * noncritical resource releasing. + */ + RelationPurgeLocalRelation(true); AtEOXact_temp_relations(true); smgrDoPendingDeletes(true); @@ -1081,23 +1092,6 @@ AbortTransaction(void) HOLD_INTERRUPTS(); /* - * Let others to know about no transaction in progress - vadim - * 11/26/96 - * - * XXX it'd be nice to acquire SInvalLock for this, but too much risk of - * lockup: what if we were holding SInvalLock when we elog'd? Net effect - * is that we are relying on fetch/store of an xid to be atomic, else - * other backends might see a partially-zeroed xid here. Would it be - * safe to release spins before we reset xid/xmin? But see also - * GetNewTransactionId, which does the same thing. - */ - if (MyProc != (PROC *) NULL) - { - MyProc->xid = InvalidTransactionId; - MyProc->xmin = InvalidTransactionId; - } - - /* * Release any spinlocks or buffer context locks we might be holding * as quickly as possible. (Real locks, however, must be held till we * finish aborting.) Releasing spinlocks is critical since we might @@ -1143,10 +1137,23 @@ AbortTransaction(void) AtAbort_Notify(); CloseSequences(); AtEOXact_portals(); + + /* Advertise the fact that we aborted in pg_log. */ RecordTransactionAbort(); - /* Count transaction abort in statistics collector */ - pgstat_count_xact_rollback(); + /* + * Let others know about no transaction in progress by me. Note that + * this must be done _before_ releasing locks we hold and _after_ + * RecordTransactionAbort. + */ + if (MyProc != (PROC *) NULL) + { + /* Lock SInvalLock because that's what GetSnapshotData uses. */ + SpinAcquire(SInvalLock); + MyProc->xid = InvalidTransactionId; + MyProc->xmin = InvalidTransactionId; + SpinRelease(SInvalLock); + } RelationPurgeLocalRelation(false); AtEOXact_temp_relations(false); @@ -1165,6 +1172,9 @@ AbortTransaction(void) SharedBufferChanged = false;/* safest place to do it */ + /* Count transaction abort in statistics collector */ + pgstat_count_xact_rollback(); + /* * State remains TRANS_ABORT until CleanupTransaction(). */ |