diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c index a6c0351c81..d4f294f4aa 100644 --- a/src/backend/replication/walreceiver.c +++ b/src/backend/replication/walreceiver.c @@ -261,7 +261,7 @@ WalReceiverMain(void) SpinLockRelease(&walrcv->mutex); - pg_atomic_init_u64(&WalRcv->writtenUpto, 0); + pg_atomic_write_u64(&WalRcv->writtenUpto, 0); /* Arrange to clean up at walreceiver exit */ on_shmem_exit(WalRcvDie, 0); @@ -1376,7 +1376,6 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS) state = WalRcv->walRcvState; receive_start_lsn = WalRcv->receiveStart; receive_start_tli = WalRcv->receiveStartTLI; - written_lsn = pg_atomic_read_u64(&WalRcv->writtenUpto); flushed_lsn = WalRcv->flushedUpto; received_tli = WalRcv->receivedTLI; last_send_time = WalRcv->lastMsgSendTime; @@ -1396,6 +1395,14 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS) if (pid == 0 || !ready_to_display) PG_RETURN_NULL(); + /* + * Read "writtenUpto" without holding a spinlock. Note that it may not be + * consistent with the other shared variables of the WAL receiver + * protected by a spinlock, but this should not be used for data integrity + * checks. + */ + written_lsn = pg_atomic_read_u64(&WalRcv->writtenUpto); + /* determine result type */ if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) elog(ERROR, "return type must be a row type"); diff --git a/src/backend/replication/walreceiverfuncs.c b/src/backend/replication/walreceiverfuncs.c index c3e317df9f..3984228a11 100644 --- a/src/backend/replication/walreceiverfuncs.c +++ b/src/backend/replication/walreceiverfuncs.c @@ -63,6 +63,7 @@ WalRcvShmemInit(void) MemSet(WalRcv, 0, WalRcvShmemSize()); WalRcv->walRcvState = WALRCV_STOPPED; SpinLockInit(&WalRcv->mutex); + pg_atomic_init_u64(&WalRcv->writtenUpto, 0); WalRcv->latch = NULL; } } diff --git a/src/test/regress/expected/sysviews.out b/src/test/regress/expected/sysviews.out index 06c4c3e476..c3b988597c 100644 --- a/src/test/regress/expected/sysviews.out +++ b/src/test/regress/expected/sysviews.out @@ -67,6 +67,13 @@ select count(*) >= 0 as ok from pg_prepared_xacts; t (1 row) +-- We expect no walreceiver running in this test +select count(*) = 0 as ok from pg_stat_wal_receiver; + ok +---- + t +(1 row) + -- This is to record the prevailing planner enable_foo settings during -- a regression test run. select name, setting from pg_settings where name like 'enable%'; diff --git a/src/test/regress/sql/sysviews.sql b/src/test/regress/sql/sysviews.sql index 28e412b735..5eb111d3fd 100644 --- a/src/test/regress/sql/sysviews.sql +++ b/src/test/regress/sql/sysviews.sql @@ -32,6 +32,9 @@ select count(*) = 0 as ok from pg_prepared_statements; -- See also prepared_xacts.sql select count(*) >= 0 as ok from pg_prepared_xacts; +-- We expect no walreceiver running in this test +select count(*) = 0 as ok from pg_stat_wal_receiver; + -- This is to record the prevailing planner enable_foo settings during -- a regression test run. select name, setting from pg_settings where name like 'enable%';