From 55d685515d9459d07863b8e9845ed9620c6eff21 Mon Sep 17 00:00:00 2001 From: Euler Taveira Date: Wed, 21 Jan 2026 10:42:02 -0300 Subject: [PATCH v9 3/3] Assign backend type earlier MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Instead of assigning the backend type into the Main function of each postmaster child, do it earlier (after fork()). The backend type is already known by postmaster_child_launch() before it calls fork(). This reduces the time frame that MyBackendType is correct. (This is important for log_min_messages per backend type that relies on a known MyBackendType to decide if it writes a log message or not.) Author: Euler Taveira Author: Álvaro Herrera Discussion: https://www.postgresql.org/message-id/flat/e85c6671-1600-4112-8887-f97a8a5d07b2@app.fastmail.com --- src/backend/postmaster/autovacuum.c | 2 -- src/backend/postmaster/bgworker.c | 1 - src/backend/postmaster/bgwriter.c | 1 - src/backend/postmaster/checkpointer.c | 1 - src/backend/postmaster/launch_backend.c | 3 +++ src/backend/postmaster/pgarch.c | 1 - src/backend/postmaster/startup.c | 1 - src/backend/postmaster/syslogger.c | 1 - src/backend/postmaster/walsummarizer.c | 1 - src/backend/postmaster/walwriter.c | 1 - src/backend/replication/logical/slotsync.c | 2 -- src/backend/replication/walreceiver.c | 1 - src/backend/storage/aio/method_worker.c | 1 - src/backend/utils/error/elog.c | 7 ++++++- 14 files changed, 9 insertions(+), 15 deletions(-) diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c index 22379de1e31..6fde740465f 100644 --- a/src/backend/postmaster/autovacuum.c +++ b/src/backend/postmaster/autovacuum.c @@ -385,7 +385,6 @@ AutoVacLauncherMain(const void *startup_data, size_t startup_data_len) PostmasterContext = NULL; } - MyBackendType = B_AUTOVAC_LAUNCHER; init_ps_display(NULL); ereport(DEBUG1, @@ -1398,7 +1397,6 @@ AutoVacWorkerMain(const void *startup_data, size_t startup_data_len) PostmasterContext = NULL; } - MyBackendType = B_AUTOVAC_WORKER; init_ps_display(NULL); Assert(GetProcessingMode() == InitProcessing); diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index 65deabe91a7..5144d70095c 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -753,7 +753,6 @@ BackgroundWorkerMain(const void *startup_data, size_t startup_data_len) } MyBgworkerEntry = worker; - MyBackendType = B_BG_WORKER; init_ps_display(worker->bgw_name); Assert(GetProcessingMode() == InitProcessing); diff --git a/src/backend/postmaster/bgwriter.c b/src/backend/postmaster/bgwriter.c index 80e3088fc7e..0956bd39a85 100644 --- a/src/backend/postmaster/bgwriter.c +++ b/src/backend/postmaster/bgwriter.c @@ -94,7 +94,6 @@ BackgroundWriterMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_BG_WRITER; AuxiliaryProcessMainCommon(); /* diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c index 6482c21b8f9..e03c19123bc 100644 --- a/src/backend/postmaster/checkpointer.c +++ b/src/backend/postmaster/checkpointer.c @@ -199,7 +199,6 @@ CheckpointerMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_CHECKPOINTER; AuxiliaryProcessMainCommon(); CheckpointerShmem->checkpointer_pid = MyProcPid; diff --git a/src/backend/postmaster/launch_backend.c b/src/backend/postmaster/launch_backend.c index 756a0237deb..66b548d0e4d 100644 --- a/src/backend/postmaster/launch_backend.c +++ b/src/backend/postmaster/launch_backend.c @@ -224,6 +224,8 @@ postmaster_child_launch(BackendType child_type, int child_slot, pid = fork_process(); if (pid == 0) /* child */ { + MyBackendType = child_type; + /* Capture and transfer timings that may be needed for logging */ if (IsExternalConnectionBackend(child_type)) { @@ -608,6 +610,7 @@ SubPostmasterMain(int argc, char *argv[]) child_type = (BackendType) atoi(child_kind); if (child_type <= B_INVALID || child_type > BACKEND_NUM_TYPES - 1) elog(ERROR, "unknown child kind %s", child_kind); + MyBackendType = child_type; /* Read in the variables file */ read_backend_variables(argv[2], &startup_data, &startup_data_len); diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c index 1a20387c4bd..82731e452fc 100644 --- a/src/backend/postmaster/pgarch.c +++ b/src/backend/postmaster/pgarch.c @@ -222,7 +222,6 @@ PgArchiverMain(const void *startup_data, size_t startup_data_len) { Assert(startup_data_len == 0); - MyBackendType = B_ARCHIVER; AuxiliaryProcessMainCommon(); /* diff --git a/src/backend/postmaster/startup.c b/src/backend/postmaster/startup.c index a1a4f65f9a9..cdbe53dd262 100644 --- a/src/backend/postmaster/startup.c +++ b/src/backend/postmaster/startup.c @@ -217,7 +217,6 @@ StartupProcessMain(const void *startup_data, size_t startup_data_len) { Assert(startup_data_len == 0); - MyBackendType = B_STARTUP; AuxiliaryProcessMainCommon(); /* Arrange to clean up at startup process exit */ diff --git a/src/backend/postmaster/syslogger.c b/src/backend/postmaster/syslogger.c index 1c443b3d126..86c5e376b40 100644 --- a/src/backend/postmaster/syslogger.c +++ b/src/backend/postmaster/syslogger.c @@ -206,7 +206,6 @@ SysLoggerMain(const void *startup_data, size_t startup_data_len) now = MyStartTime; - MyBackendType = B_LOGGER; init_ps_display(NULL); /* diff --git a/src/backend/postmaster/walsummarizer.c b/src/backend/postmaster/walsummarizer.c index c3d56c866d3..2d8f57099fd 100644 --- a/src/backend/postmaster/walsummarizer.c +++ b/src/backend/postmaster/walsummarizer.c @@ -234,7 +234,6 @@ WalSummarizerMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_WAL_SUMMARIZER; AuxiliaryProcessMainCommon(); ereport(DEBUG1, diff --git a/src/backend/postmaster/walwriter.c b/src/backend/postmaster/walwriter.c index 38ec8a4c8c7..23e79a32345 100644 --- a/src/backend/postmaster/walwriter.c +++ b/src/backend/postmaster/walwriter.c @@ -94,7 +94,6 @@ WalWriterMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_WAL_WRITER; AuxiliaryProcessMainCommon(); /* diff --git a/src/backend/replication/logical/slotsync.c b/src/backend/replication/logical/slotsync.c index 73fc51ea53e..b53f888b804 100644 --- a/src/backend/replication/logical/slotsync.c +++ b/src/backend/replication/logical/slotsync.c @@ -1540,8 +1540,6 @@ ReplSlotSyncWorkerMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_SLOTSYNC_WORKER; - init_ps_display(NULL); Assert(GetProcessingMode() == InitProcessing); diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c index a41453530a1..8dbd8cb2009 100644 --- a/src/backend/replication/walreceiver.c +++ b/src/backend/replication/walreceiver.c @@ -169,7 +169,6 @@ WalReceiverMain(const void *startup_data, size_t startup_data_len) Assert(startup_data_len == 0); - MyBackendType = B_WAL_RECEIVER; AuxiliaryProcessMainCommon(); /* diff --git a/src/backend/storage/aio/method_worker.c b/src/backend/storage/aio/method_worker.c index d7c144cd8f7..d9617c20e76 100644 --- a/src/backend/storage/aio/method_worker.c +++ b/src/backend/storage/aio/method_worker.c @@ -390,7 +390,6 @@ IoWorkerMain(const void *startup_data, size_t startup_data_len) volatile int error_errno = 0; char cmd[128]; - MyBackendType = B_IO_WORKER; AuxiliaryProcessMainCommon(); pqsignal(SIGHUP, SignalHandlerForConfigReload); diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c index 59975309a4e..f35ec0429b2 100644 --- a/src/backend/utils/error/elog.c +++ b/src/backend/utils/error/elog.c @@ -2779,7 +2779,12 @@ get_backend_type_for_log(void) if (MyProcPid == PostmasterPid) backend_type_str = "postmaster"; else if (MyBackendType == B_BG_WORKER) - backend_type_str = MyBgworkerEntry->bgw_type; + { + if (MyBgworkerEntry && MyBgworkerEntry->bgw_type[0] != '\0') + backend_type_str = MyBgworkerEntry->bgw_type; + else + backend_type_str = "early bgworker"; + } else backend_type_str = GetBackendTypeDesc(MyBackendType); -- 2.39.5