diff options
Diffstat (limited to 'src/backend/storage/lmgr/proc.c')
| -rw-r--r-- | src/backend/storage/lmgr/proc.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index c87ffc65491..f059d60a0f6 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -402,6 +402,7 @@ InitProcess(void) MyProc->lwWaitMode = 0; MyProc->waitLock = NULL; MyProc->waitProcLock = NULL; + pg_atomic_init_u64(&MyProc->waitStart, 0); #ifdef USE_ASSERT_CHECKING { int i; @@ -1262,6 +1263,23 @@ ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable) } else enable_timeout_after(DEADLOCK_TIMEOUT, DeadlockTimeout); + + /* + * Use the current time obtained for the deadlock timeout timer as + * waitStart (i.e., the time when this process started waiting for the + * lock). Since getting the current time newly can cause overhead, we + * reuse the already-obtained time to avoid that overhead. + * + * Note that waitStart is updated without holding the lock table's + * partition lock, to avoid the overhead by additional lock + * acquisition. This can cause "waitstart" in pg_locks to become NULL + * for a very short period of time after the wait started even though + * "granted" is false. This is OK in practice because we can assume + * that users are likely to look at "waitstart" when waiting for the + * lock for a long time. + */ + pg_atomic_write_u64(&MyProc->waitStart, + get_timeout_start_time(DEADLOCK_TIMEOUT)); } else if (log_recovery_conflict_waits) { @@ -1678,6 +1696,7 @@ ProcWakeup(PGPROC *proc, ProcWaitStatus waitStatus) proc->waitLock = NULL; proc->waitProcLock = NULL; proc->waitStatus = waitStatus; + pg_atomic_write_u64(&MyProc->waitStart, 0); /* And awaken it */ SetLatch(&proc->procLatch); |