diff options
Diffstat (limited to 'src/backend/storage/ipc')
| -rw-r--r-- | src/backend/storage/ipc/procarray.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index 96b22d3881e..b6d7198c3fc 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -102,6 +102,11 @@ static PGPROC *allProcs; static PGXACT *allPgXact; /* + * Cache to reduce overhead of repeated calls to TransactionIdIsInProgress() + */ +static TransactionId cachedXidIsNotInProgress = InvalidTransactionId; + +/* * Bookkeeping for tracking emulated transactions in recovery */ static TransactionId *KnownAssignedXids; @@ -1029,7 +1034,7 @@ TransactionIdIsInProgress(TransactionId xid) * already known to be completed, we can fall out without any access to * shared memory. */ - if (TransactionIdIsKnownCompleted(xid)) + if (TransactionIdEquals(cachedXidIsNotInProgress, xid)) { xc_by_known_xact_inc(); return false; @@ -1179,6 +1184,7 @@ TransactionIdIsInProgress(TransactionId xid) if (nxids == 0) { xc_no_overflow_inc(); + cachedXidIsNotInProgress = xid; return false; } @@ -1193,7 +1199,10 @@ TransactionIdIsInProgress(TransactionId xid) xc_slow_answer_inc(); if (TransactionIdDidAbort(xid)) + { + cachedXidIsNotInProgress = xid; return false; + } /* * It isn't aborted, so check whether the transaction tree it belongs to @@ -1211,6 +1220,7 @@ TransactionIdIsInProgress(TransactionId xid) } } + cachedXidIsNotInProgress = xid; return false; } |