Split wait event related code from pgstat.[ch] into wait_event.[ch].

The wait event related code is independent from the rest of the
pgstat.[ch] code, of nontrivial size and changes on a regular
basis. Put it into its own set of files.

As there doesn't seem to be a good pre-existing directory for code
like this, add src/backend/utils/activity.

Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/20210316195440.twxmlov24rr2nxrg@alap3.anarazel.de

4 files changed, 723 insertions, 674 deletions

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 2f3f378e633..de239136f48 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -352,12 +352,6 @@ static PgStat_TableStatus *get_tabstat_entry(Oid rel_id, bool isshared);
 
 static void pgstat_setup_memcxt(void);
 
-static const char *pgstat_get_wait_activity(WaitEventActivity w);
-static const char *pgstat_get_wait_client(WaitEventClient w);
-static const char *pgstat_get_wait_ipc(WaitEventIPC w);
-static const char *pgstat_get_wait_timeout(WaitEventTimeout w);
-static const char *pgstat_get_wait_io(WaitEventIO w);
-
 static void pgstat_setheader(PgStat_MsgHdr *hdr, StatMsgType mtype);
 static void pgstat_send(void *msg, int len);
 
@@ -3752,673 +3746,6 @@ pgstat_read_current_status(void)
 }
 
 /* ----------
- * pgstat_get_wait_event_type() -
- *
- *	Return a string representing the current wait event type, backend is
- *	waiting on.
- */
-const char *
-pgstat_get_wait_event_type(uint32 wait_event_info)
-{
-	uint32		classId;
-	const char *event_type;
-
-	/* report process as not waiting. */
-	if (wait_event_info == 0)
-		return NULL;
-
-	classId = wait_event_info & 0xFF000000;
-
-	switch (classId)
-	{
-		case PG_WAIT_LWLOCK:
-			event_type = "LWLock";
-			break;
-		case PG_WAIT_LOCK:
-			event_type = "Lock";
-			break;
-		case PG_WAIT_BUFFER_PIN:
-			event_type = "BufferPin";
-			break;
-		case PG_WAIT_ACTIVITY:
-			event_type = "Activity";
-			break;
-		case PG_WAIT_CLIENT:
-			event_type = "Client";
-			break;
-		case PG_WAIT_EXTENSION:
-			event_type = "Extension";
-			break;
-		case PG_WAIT_IPC:
-			event_type = "IPC";
-			break;
-		case PG_WAIT_TIMEOUT:
-			event_type = "Timeout";
-			break;
-		case PG_WAIT_IO:
-			event_type = "IO";
-			break;
-		default:
-			event_type = "???";
-			break;
-	}
-
-	return event_type;
-}
-
-/* ----------
- * pgstat_get_wait_event() -
- *
- *	Return a string representing the current wait event, backend is
- *	waiting on.
- */
-const char *
-pgstat_get_wait_event(uint32 wait_event_info)
-{
-	uint32		classId;
-	uint16		eventId;
-	const char *event_name;
-
-	/* report process as not waiting. */
-	if (wait_event_info == 0)
-		return NULL;
-
-	classId = wait_event_info & 0xFF000000;
-	eventId = wait_event_info & 0x0000FFFF;
-
-	switch (classId)
-	{
-		case PG_WAIT_LWLOCK:
-			event_name = GetLWLockIdentifier(classId, eventId);
-			break;
-		case PG_WAIT_LOCK:
-			event_name = GetLockNameFromTagType(eventId);
-			break;
-		case PG_WAIT_BUFFER_PIN:
-			event_name = "BufferPin";
-			break;
-		case PG_WAIT_ACTIVITY:
-			{
-				WaitEventActivity w = (WaitEventActivity) wait_event_info;
-
-				event_name = pgstat_get_wait_activity(w);
-				break;
-			}
-		case PG_WAIT_CLIENT:
-			{
-				WaitEventClient w = (WaitEventClient) wait_event_info;
-
-				event_name = pgstat_get_wait_client(w);
-				break;
-			}
-		case PG_WAIT_EXTENSION:
-			event_name = "Extension";
-			break;
-		case PG_WAIT_IPC:
-			{
-				WaitEventIPC w = (WaitEventIPC) wait_event_info;
-
-				event_name = pgstat_get_wait_ipc(w);
-				break;
-			}
-		case PG_WAIT_TIMEOUT:
-			{
-				WaitEventTimeout w = (WaitEventTimeout) wait_event_info;
-
-				event_name = pgstat_get_wait_timeout(w);
-				break;
-			}
-		case PG_WAIT_IO:
-			{
-				WaitEventIO w = (WaitEventIO) wait_event_info;
-
-				event_name = pgstat_get_wait_io(w);
-				break;
-			}
-		default:
-			event_name = "unknown wait event";
-			break;
-	}
-
-	return event_name;
-}
-
-/* ----------
- * pgstat_get_wait_activity() -
- *
- * Convert WaitEventActivity to string.
- * ----------
- */
-static const char *
-pgstat_get_wait_activity(WaitEventActivity w)
-{
-	const char *event_name = "unknown wait event";
-
-	switch (w)
-	{
-		case WAIT_EVENT_ARCHIVER_MAIN:
-			event_name = "ArchiverMain";
-			break;
-		case WAIT_EVENT_AUTOVACUUM_MAIN:
-			event_name = "AutoVacuumMain";
-			break;
-		case WAIT_EVENT_BGWRITER_HIBERNATE:
-			event_name = "BgWriterHibernate";
-			break;
-		case WAIT_EVENT_BGWRITER_MAIN:
-			event_name = "BgWriterMain";
-			break;
-		case WAIT_EVENT_CHECKPOINTER_MAIN:
-			event_name = "CheckpointerMain";
-			break;
-		case WAIT_EVENT_LOGICAL_APPLY_MAIN:
-			event_name = "LogicalApplyMain";
-			break;
-		case WAIT_EVENT_LOGICAL_LAUNCHER_MAIN:
-			event_name = "LogicalLauncherMain";
-			break;
-		case WAIT_EVENT_PGSTAT_MAIN:
-			event_name = "PgStatMain";
-			break;
-		case WAIT_EVENT_RECOVERY_WAL_STREAM:
-			event_name = "RecoveryWalStream";
-			break;
-		case WAIT_EVENT_SYSLOGGER_MAIN:
-			event_name = "SysLoggerMain";
-			break;
-		case WAIT_EVENT_WAL_RECEIVER_MAIN:
-			event_name = "WalReceiverMain";
-			break;
-		case WAIT_EVENT_WAL_SENDER_MAIN:
-			event_name = "WalSenderMain";
-			break;
-		case WAIT_EVENT_WAL_WRITER_MAIN:
-			event_name = "WalWriterMain";
-			break;
-			/* no default case, so that compiler will warn */
-	}
-
-	return event_name;
-}
-
-/* ----------
- * pgstat_get_wait_client() -
- *
- * Convert WaitEventClient to string.
- * ----------
- */
-static const char *
-pgstat_get_wait_client(WaitEventClient w)
-{
-	const char *event_name = "unknown wait event";
-
-	switch (w)
-	{
-		case WAIT_EVENT_CLIENT_READ:
-			event_name = "ClientRead";
-			break;
-		case WAIT_EVENT_CLIENT_WRITE:
-			event_name = "ClientWrite";
-			break;
-		case WAIT_EVENT_GSS_OPEN_SERVER:
-			event_name = "GSSOpenServer";
-			break;
-		case WAIT_EVENT_LIBPQWALRECEIVER_CONNECT:
-			event_name = "LibPQWalReceiverConnect";
-			break;
-		case WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE:
-			event_name = "LibPQWalReceiverReceive";
-			break;
-		case WAIT_EVENT_SSL_OPEN_SERVER:
-			event_name = "SSLOpenServer";
-			break;
-		case WAIT_EVENT_WAL_SENDER_WAIT_WAL:
-			event_name = "WalSenderWaitForWAL";
-			break;
-		case WAIT_EVENT_WAL_SENDER_WRITE_DATA:
-			event_name = "WalSenderWriteData";
-			break;
-			/* no default case, so that compiler will warn */
-	}
-
-	return event_name;
-}
-
-/* ----------
- * pgstat_get_wait_ipc() -
- *
- * Convert WaitEventIPC to string.
- * ----------
- */
-static const char *
-pgstat_get_wait_ipc(WaitEventIPC w)
-{
-	const char *event_name = "unknown wait event";
-
-	switch (w)
-	{
-		case WAIT_EVENT_APPEND_READY:
-			event_name = "AppendReady";
-			break;
-		case WAIT_EVENT_BACKUP_WAIT_WAL_ARCHIVE:
-			event_name = "BackupWaitWalArchive";
-			break;
-		case WAIT_EVENT_BGWORKER_SHUTDOWN:
-			event_name = "BgWorkerShutdown";
-			break;
-		case WAIT_EVENT_BGWORKER_STARTUP:
-			event_name = "BgWorkerStartup";
-			break;
-		case WAIT_EVENT_BTREE_PAGE:
-			event_name = "BtreePage";
-			break;
-		case WAIT_EVENT_BUFFER_IO:
-			event_name = "BufferIO";
-			break;
-		case WAIT_EVENT_CHECKPOINT_DONE:
-			event_name = "CheckpointDone";
-			break;
-		case WAIT_EVENT_CHECKPOINT_START:
-			event_name = "CheckpointStart";
-			break;
-		case WAIT_EVENT_EXECUTE_GATHER:
-			event_name = "ExecuteGather";
-			break;
-		case WAIT_EVENT_HASH_BATCH_ALLOCATE:
-			event_name = "HashBatchAllocate";
-			break;
-		case WAIT_EVENT_HASH_BATCH_ELECT:
-			event_name = "HashBatchElect";
-			break;
-		case WAIT_EVENT_HASH_BATCH_LOAD:
-			event_name = "HashBatchLoad";
-			break;
-		case WAIT_EVENT_HASH_BUILD_ALLOCATE:
-			event_name = "HashBuildAllocate";
-			break;
-		case WAIT_EVENT_HASH_BUILD_ELECT:
-			event_name = "HashBuildElect";
-			break;
-		case WAIT_EVENT_HASH_BUILD_HASH_INNER:
-			event_name = "HashBuildHashInner";
-			break;
-		case WAIT_EVENT_HASH_BUILD_HASH_OUTER:
-			event_name = "HashBuildHashOuter";
-			break;
-		case WAIT_EVENT_HASH_GROW_BATCHES_ALLOCATE:
-			event_name = "HashGrowBatchesAllocate";
-			break;
-		case WAIT_EVENT_HASH_GROW_BATCHES_DECIDE:
-			event_name = "HashGrowBatchesDecide";
-			break;
-		case WAIT_EVENT_HASH_GROW_BATCHES_ELECT:
-			event_name = "HashGrowBatchesElect";
-			break;
-		case WAIT_EVENT_HASH_GROW_BATCHES_FINISH:
-			event_name = "HashGrowBatchesFinish";
-			break;
-		case WAIT_EVENT_HASH_GROW_BATCHES_REPARTITION:
-			event_name = "HashGrowBatchesRepartition";
-			break;
-		case WAIT_EVENT_HASH_GROW_BUCKETS_ALLOCATE:
-			event_name = "HashGrowBucketsAllocate";
-			break;
-		case WAIT_EVENT_HASH_GROW_BUCKETS_ELECT:
-			event_name = "HashGrowBucketsElect";
-			break;
-		case WAIT_EVENT_HASH_GROW_BUCKETS_REINSERT:
-			event_name = "HashGrowBucketsReinsert";
-			break;
-		case WAIT_EVENT_LOGICAL_SYNC_DATA:
-			event_name = "LogicalSyncData";
-			break;
-		case WAIT_EVENT_LOGICAL_SYNC_STATE_CHANGE:
-			event_name = "LogicalSyncStateChange";
-			break;
-		case WAIT_EVENT_MQ_INTERNAL:
-			event_name = "MessageQueueInternal";
-			break;
-		case WAIT_EVENT_MQ_PUT_MESSAGE:
-			event_name = "MessageQueuePutMessage";
-			break;
-		case WAIT_EVENT_MQ_RECEIVE:
-			event_name = "MessageQueueReceive";
-			break;
-		case WAIT_EVENT_MQ_SEND:
-			event_name = "MessageQueueSend";
-			break;
-		case WAIT_EVENT_PARALLEL_BITMAP_SCAN:
-			event_name = "ParallelBitmapScan";
-			break;
-		case WAIT_EVENT_PARALLEL_CREATE_INDEX_SCAN:
-			event_name = "ParallelCreateIndexScan";
-			break;
-		case WAIT_EVENT_PARALLEL_FINISH:
-			event_name = "ParallelFinish";
-			break;
-		case WAIT_EVENT_PROCARRAY_GROUP_UPDATE:
-			event_name = "ProcArrayGroupUpdate";
-			break;
-		case WAIT_EVENT_PROC_SIGNAL_BARRIER:
-			event_name = "ProcSignalBarrier";
-			break;
-		case WAIT_EVENT_PROMOTE:
-			event_name = "Promote";
-			break;
-		case WAIT_EVENT_RECOVERY_CONFLICT_SNAPSHOT:
-			event_name = "RecoveryConflictSnapshot";
-			break;
-		case WAIT_EVENT_RECOVERY_CONFLICT_TABLESPACE:
-			event_name = "RecoveryConflictTablespace";
-			break;
-		case WAIT_EVENT_RECOVERY_PAUSE:
-			event_name = "RecoveryPause";
-			break;
-		case WAIT_EVENT_REPLICATION_ORIGIN_DROP:
-			event_name = "ReplicationOriginDrop";
-			break;
-		case WAIT_EVENT_REPLICATION_SLOT_DROP:
-			event_name = "ReplicationSlotDrop";
-			break;
-		case WAIT_EVENT_SAFE_SNAPSHOT:
-			event_name = "SafeSnapshot";
-			break;
-		case WAIT_EVENT_SYNC_REP:
-			event_name = "SyncRep";
-			break;
-		case WAIT_EVENT_WAL_RECEIVER_EXIT:
-			event_name = "WalReceiverExit";
-			break;
-		case WAIT_EVENT_WAL_RECEIVER_WAIT_START:
-			event_name = "WalReceiverWaitStart";
-			break;
-		case WAIT_EVENT_XACT_GROUP_UPDATE:
-			event_name = "XactGroupUpdate";
-			break;
-			/* no default case, so that compiler will warn */
-	}
-
-	return event_name;
-}
-
-/* ----------
- * pgstat_get_wait_timeout() -
- *
- * Convert WaitEventTimeout to string.
- * ----------
- */
-static const char *
-pgstat_get_wait_timeout(WaitEventTimeout w)
-{
-	const char *event_name = "unknown wait event";
-
-	switch (w)
-	{
-		case WAIT_EVENT_BASE_BACKUP_THROTTLE:
-			event_name = "BaseBackupThrottle";
-			break;
-		case WAIT_EVENT_PG_SLEEP:
-			event_name = "PgSleep";
-			break;
-		case WAIT_EVENT_RECOVERY_APPLY_DELAY:
-			event_name = "RecoveryApplyDelay";
-			break;
-		case WAIT_EVENT_RECOVERY_RETRIEVE_RETRY_INTERVAL:
-			event_name = "RecoveryRetrieveRetryInterval";
-			break;
-		case WAIT_EVENT_VACUUM_DELAY:
-			event_name = "VacuumDelay";
-			break;
-			/* no default case, so that compiler will warn */
-	}
-
-	return event_name;
-}
-
-/* ----------
- * pgstat_get_wait_io() -
- *
- * Convert WaitEventIO to string.
- * ----------
- */
-static const char *
-pgstat_get_wait_io(WaitEventIO w)
-{
-	const char *event_name = "unknown wait event";
-
-	switch (w)
-	{
-		case WAIT_EVENT_BASEBACKUP_READ:
-			event_name = "BaseBackupRead";
-			break;
-		case WAIT_EVENT_BUFFILE_READ:
-			event_name = "BufFileRead";
-			break;
-		case WAIT_EVENT_BUFFILE_WRITE:
-			event_name = "BufFileWrite";
-			break;
-		case WAIT_EVENT_BUFFILE_TRUNCATE:
-			event_name = "BufFileTruncate";
-			break;
-		case WAIT_EVENT_CONTROL_FILE_READ:
-			event_name = "ControlFileRead";
-			break;
-		case WAIT_EVENT_CONTROL_FILE_SYNC:
-			event_name = "ControlFileSync";
-			break;
-		case WAIT_EVENT_CONTROL_FILE_SYNC_UPDATE:
-			event_name = "ControlFileSyncUpdate";
-			break;
-		case WAIT_EVENT_CONTROL_FILE_WRITE:
-			event_name = "ControlFileWrite";
-			break;
-		case WAIT_EVENT_CONTROL_FILE_WRITE_UPDATE:
-			event_name = "ControlFileWriteUpdate";
-			break;
-		case WAIT_EVENT_COPY_FILE_READ:
-			event_name = "CopyFileRead";
-			break;
-		case WAIT_EVENT_COPY_FILE_WRITE:
-			event_name = "CopyFileWrite";
-			break;
-		case WAIT_EVENT_DATA_FILE_EXTEND:
-			event_name = "DataFileExtend";
-			break;
-		case WAIT_EVENT_DATA_FILE_FLUSH:
-			event_name = "DataFileFlush";
-			break;
-		case WAIT_EVENT_DATA_FILE_IMMEDIATE_SYNC:
-			event_name = "DataFileImmediateSync";
-			break;
-		case WAIT_EVENT_DATA_FILE_PREFETCH:
-			event_name = "DataFilePrefetch";
-			break;
-		case WAIT_EVENT_DATA_FILE_READ:
-			event_name = "DataFileRead";
-			break;
-		case WAIT_EVENT_DATA_FILE_SYNC:
-			event_name = "DataFileSync";
-			break;
-		case WAIT_EVENT_DATA_FILE_TRUNCATE:
-			event_name = "DataFileTruncate";
-			break;
-		case WAIT_EVENT_DATA_FILE_WRITE:
-			event_name = "DataFileWrite";
-			break;
-		case WAIT_EVENT_DSM_FILL_ZERO_WRITE:
-			event_name = "DSMFillZeroWrite";
-			break;
-		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_READ:
-			event_name = "LockFileAddToDataDirRead";
-			break;
-		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_SYNC:
-			event_name = "LockFileAddToDataDirSync";
-			break;
-		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_WRITE:
-			event_name = "LockFileAddToDataDirWrite";
-			break;
-		case WAIT_EVENT_LOCK_FILE_CREATE_READ:
-			event_name = "LockFileCreateRead";
-			break;
-		case WAIT_EVENT_LOCK_FILE_CREATE_SYNC:
-			event_name = "LockFileCreateSync";
-			break;
-		case WAIT_EVENT_LOCK_FILE_CREATE_WRITE:
-			event_name = "LockFileCreateWrite";
-			break;
-		case WAIT_EVENT_LOCK_FILE_RECHECKDATADIR_READ:
-			event_name = "LockFileReCheckDataDirRead";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_CHECKPOINT_SYNC:
-			event_name = "LogicalRewriteCheckpointSync";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_SYNC:
-			event_name = "LogicalRewriteMappingSync";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_WRITE:
-			event_name = "LogicalRewriteMappingWrite";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_SYNC:
-			event_name = "LogicalRewriteSync";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_TRUNCATE:
-			event_name = "LogicalRewriteTruncate";
-			break;
-		case WAIT_EVENT_LOGICAL_REWRITE_WRITE:
-			event_name = "LogicalRewriteWrite";
-			break;
-		case WAIT_EVENT_RELATION_MAP_READ:
-			event_name = "RelationMapRead";
-			break;
-		case WAIT_EVENT_RELATION_MAP_SYNC:
-			event_name = "RelationMapSync";
-			break;
-		case WAIT_EVENT_RELATION_MAP_WRITE:
-			event_name = "RelationMapWrite";
-			break;
-		case WAIT_EVENT_REORDER_BUFFER_READ:
-			event_name = "ReorderBufferRead";
-			break;
-		case WAIT_EVENT_REORDER_BUFFER_WRITE:
-			event_name = "ReorderBufferWrite";
-			break;
-		case WAIT_EVENT_REORDER_LOGICAL_MAPPING_READ:
-			event_name = "ReorderLogicalMappingRead";
-			break;
-		case WAIT_EVENT_REPLICATION_SLOT_READ:
-			event_name = "ReplicationSlotRead";
-			break;
-		case WAIT_EVENT_REPLICATION_SLOT_RESTORE_SYNC:
-			event_name = "ReplicationSlotRestoreSync";
-			break;
-		case WAIT_EVENT_REPLICATION_SLOT_SYNC:
-			event_name = "ReplicationSlotSync";
-			break;
-		case WAIT_EVENT_REPLICATION_SLOT_WRITE:
-			event_name = "ReplicationSlotWrite";
-			break;
-		case WAIT_EVENT_SLRU_FLUSH_SYNC:
-			event_name = "SLRUFlushSync";
-			break;
-		case WAIT_EVENT_SLRU_READ:
-			event_name = "SLRURead";
-			break;
-		case WAIT_EVENT_SLRU_SYNC:
-			event_name = "SLRUSync";
-			break;
-		case WAIT_EVENT_SLRU_WRITE:
-			event_name = "SLRUWrite";
-			break;
-		case WAIT_EVENT_SNAPBUILD_READ:
-			event_name = "SnapbuildRead";
-			break;
-		case WAIT_EVENT_SNAPBUILD_SYNC:
-			event_name = "SnapbuildSync";
-			break;
-		case WAIT_EVENT_SNAPBUILD_WRITE:
-			event_name = "SnapbuildWrite";
-			break;
-		case WAIT_EVENT_TIMELINE_HISTORY_FILE_SYNC:
-			event_name = "TimelineHistoryFileSync";
-			break;
-		case WAIT_EVENT_TIMELINE_HISTORY_FILE_WRITE:
-			event_name = "TimelineHistoryFileWrite";
-			break;
-		case WAIT_EVENT_TIMELINE_HISTORY_READ:
-			event_name = "TimelineHistoryRead";
-			break;
-		case WAIT_EVENT_TIMELINE_HISTORY_SYNC:
-			event_name = "TimelineHistorySync";
-			break;
-		case WAIT_EVENT_TIMELINE_HISTORY_WRITE:
-			event_name = "TimelineHistoryWrite";
-			break;
-		case WAIT_EVENT_TWOPHASE_FILE_READ:
-			event_name = "TwophaseFileRead";
-			break;
-		case WAIT_EVENT_TWOPHASE_FILE_SYNC:
-			event_name = "TwophaseFileSync";
-			break;
-		case WAIT_EVENT_TWOPHASE_FILE_WRITE:
-			event_name = "TwophaseFileWrite";
-			break;
-		case WAIT_EVENT_WALSENDER_TIMELINE_HISTORY_READ:
-			event_name = "WALSenderTimelineHistoryRead";
-			break;
-		case WAIT_EVENT_WAL_BOOTSTRAP_SYNC:
-			event_name = "WALBootstrapSync";
-			break;
-		case WAIT_EVENT_WAL_BOOTSTRAP_WRITE:
-			event_name = "WALBootstrapWrite";
-			break;
-		case WAIT_EVENT_WAL_COPY_READ:
-			event_name = "WALCopyRead";
-			break;
-		case WAIT_EVENT_WAL_COPY_SYNC:
-			event_name = "WALCopySync";
-			break;
-		case WAIT_EVENT_WAL_COPY_WRITE:
-			event_name = "WALCopyWrite";
-			break;
-		case WAIT_EVENT_WAL_INIT_SYNC:
-			event_name = "WALInitSync";
-			break;
-		case WAIT_EVENT_WAL_INIT_WRITE:
-			event_name = "WALInitWrite";
-			break;
-		case WAIT_EVENT_WAL_READ:
-			event_name = "WALRead";
-			break;
-		case WAIT_EVENT_WAL_SYNC:
-			event_name = "WALSync";
-			break;
-		case WAIT_EVENT_WAL_SYNC_METHOD_ASSIGN:
-			event_name = "WALSyncMethodAssign";
-			break;
-		case WAIT_EVENT_WAL_WRITE:
-			event_name = "WALWrite";
-			break;
-		case WAIT_EVENT_LOGICAL_CHANGES_READ:
-			event_name = "LogicalChangesRead";
-			break;
-		case WAIT_EVENT_LOGICAL_CHANGES_WRITE:
-			event_name = "LogicalChangesWrite";
-			break;
-		case WAIT_EVENT_LOGICAL_SUBXACT_READ:
-			event_name = "LogicalSubxactRead";
-			break;
-		case WAIT_EVENT_LOGICAL_SUBXACT_WRITE:
-			event_name = "LogicalSubxactWrite";
-			break;
-
-			/* no default case, so that compiler will warn */
-	}
-
-	return event_name;
-}
-
-
-/* ----------
  * pgstat_get_backend_current_activity() -
  *
  *	Return a string representing the current activity of the backend with
diff --git a/src/backend/utils/Makefile b/src/backend/utils/Makefile
index 26e07100a5d..59b22552606 100644
--- a/src/backend/utils/Makefile
+++ b/src/backend/utils/Makefile
@@ -14,7 +14,20 @@ top_builddir = ../../..
 include $(top_builddir)/src/Makefile.global
 
 OBJS        = fmgrtab.o
-SUBDIRS     = adt cache error fmgr hash init mb misc mmgr resowner sort time
+SUBDIRS     = \
+	activity \
+	adt \
+	cache \
+	error \
+	fmgr \
+	hash \
+	init \
+	mb \
+	misc \
+	mmgr \
+	resowner \
+	sort \
+	time
 
 # location of Catalog.pm
 catalogdir  = $(top_srcdir)/src/backend/catalog
diff --git a/src/backend/utils/activity/Makefile b/src/backend/utils/activity/Makefile
new file mode 100644
index 00000000000..7cbe0cdbe81
--- /dev/null
+++ b/src/backend/utils/activity/Makefile
@@ -0,0 +1,19 @@
+#-------------------------------------------------------------------------
+#
+# Makefile for backend/utils/activity
+#
+# Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+# Portions Copyright (c) 1994, Regents of the University of California
+#
+# src/backend/utils/activity/Makefile
+#
+#-------------------------------------------------------------------------
+
+subdir = src/backend/utils/activity
+top_builddir = ../../../..
+include $(top_builddir)/src/Makefile.global
+
+OBJS = \
+	wait_event.o
+
+include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/utils/activity/wait_event.c b/src/backend/utils/activity/wait_event.c
new file mode 100644
index 00000000000..840ebef92ab
--- /dev/null
+++ b/src/backend/utils/activity/wait_event.c
@@ -0,0 +1,690 @@
+/* ----------
+ * wait_event.c
+ *	  Wait event reporting infrastructure.
+ *
+ * Copyright (c) 2001-2021, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/postmaster/wait_event.c
+ * ----------
+ */
+#include "postgres.h"
+
+#include "storage/lmgr.h" /* for GetLockNameFromTagType */
+#include "storage/lwlock.h" /* for GetLWLockIdentifier */
+#include "utils/wait_event.h"
+
+
+static const char *pgstat_get_wait_activity(WaitEventActivity w);
+static const char *pgstat_get_wait_client(WaitEventClient w);
+static const char *pgstat_get_wait_ipc(WaitEventIPC w);
+static const char *pgstat_get_wait_timeout(WaitEventTimeout w);
+static const char *pgstat_get_wait_io(WaitEventIO w);
+
+
+/* ----------
+ * pgstat_get_wait_event_type() -
+ *
+ *	Return a string representing the current wait event type, backend is
+ *	waiting on.
+ */
+const char *
+pgstat_get_wait_event_type(uint32 wait_event_info)
+{
+	uint32		classId;
+	const char *event_type;
+
+	/* report process as not waiting. */
+	if (wait_event_info == 0)
+		return NULL;
+
+	classId = wait_event_info & 0xFF000000;
+
+	switch (classId)
+	{
+		case PG_WAIT_LWLOCK:
+			event_type = "LWLock";
+			break;
+		case PG_WAIT_LOCK:
+			event_type = "Lock";
+			break;
+		case PG_WAIT_BUFFER_PIN:
+			event_type = "BufferPin";
+			break;
+		case PG_WAIT_ACTIVITY:
+			event_type = "Activity";
+			break;
+		case PG_WAIT_CLIENT:
+			event_type = "Client";
+			break;
+		case PG_WAIT_EXTENSION:
+			event_type = "Extension";
+			break;
+		case PG_WAIT_IPC:
+			event_type = "IPC";
+			break;
+		case PG_WAIT_TIMEOUT:
+			event_type = "Timeout";
+			break;
+		case PG_WAIT_IO:
+			event_type = "IO";
+			break;
+		default:
+			event_type = "???";
+			break;
+	}
+
+	return event_type;
+}
+
+/* ----------
+ * pgstat_get_wait_event() -
+ *
+ *	Return a string representing the current wait event, backend is
+ *	waiting on.
+ */
+const char *
+pgstat_get_wait_event(uint32 wait_event_info)
+{
+	uint32		classId;
+	uint16		eventId;
+	const char *event_name;
+
+	/* report process as not waiting. */
+	if (wait_event_info == 0)
+		return NULL;
+
+	classId = wait_event_info & 0xFF000000;
+	eventId = wait_event_info & 0x0000FFFF;
+
+	switch (classId)
+	{
+		case PG_WAIT_LWLOCK:
+			event_name = GetLWLockIdentifier(classId, eventId);
+			break;
+		case PG_WAIT_LOCK:
+			event_name = GetLockNameFromTagType(eventId);
+			break;
+		case PG_WAIT_BUFFER_PIN:
+			event_name = "BufferPin";
+			break;
+		case PG_WAIT_ACTIVITY:
+			{
+				WaitEventActivity w = (WaitEventActivity) wait_event_info;
+
+				event_name = pgstat_get_wait_activity(w);
+				break;
+			}
+		case PG_WAIT_CLIENT:
+			{
+				WaitEventClient w = (WaitEventClient) wait_event_info;
+
+				event_name = pgstat_get_wait_client(w);
+				break;
+			}
+		case PG_WAIT_EXTENSION:
+			event_name = "Extension";
+			break;
+		case PG_WAIT_IPC:
+			{
+				WaitEventIPC w = (WaitEventIPC) wait_event_info;
+
+				event_name = pgstat_get_wait_ipc(w);
+				break;
+			}
+		case PG_WAIT_TIMEOUT:
+			{
+				WaitEventTimeout w = (WaitEventTimeout) wait_event_info;
+
+				event_name = pgstat_get_wait_timeout(w);
+				break;
+			}
+		case PG_WAIT_IO:
+			{
+				WaitEventIO w = (WaitEventIO) wait_event_info;
+
+				event_name = pgstat_get_wait_io(w);
+				break;
+			}
+		default:
+			event_name = "unknown wait event";
+			break;
+	}
+
+	return event_name;
+}
+
+/* ----------
+ * pgstat_get_wait_activity() -
+ *
+ * Convert WaitEventActivity to string.
+ * ----------
+ */
+static const char *
+pgstat_get_wait_activity(WaitEventActivity w)
+{
+	const char *event_name = "unknown wait event";
+
+	switch (w)
+	{
+		case WAIT_EVENT_ARCHIVER_MAIN:
+			event_name = "ArchiverMain";
+			break;
+		case WAIT_EVENT_AUTOVACUUM_MAIN:
+			event_name = "AutoVacuumMain";
+			break;
+		case WAIT_EVENT_BGWRITER_HIBERNATE:
+			event_name = "BgWriterHibernate";
+			break;
+		case WAIT_EVENT_BGWRITER_MAIN:
+			event_name = "BgWriterMain";
+			break;
+		case WAIT_EVENT_CHECKPOINTER_MAIN:
+			event_name = "CheckpointerMain";
+			break;
+		case WAIT_EVENT_LOGICAL_APPLY_MAIN:
+			event_name = "LogicalApplyMain";
+			break;
+		case WAIT_EVENT_LOGICAL_LAUNCHER_MAIN:
+			event_name = "LogicalLauncherMain";
+			break;
+		case WAIT_EVENT_PGSTAT_MAIN:
+			event_name = "PgStatMain";
+			break;
+		case WAIT_EVENT_RECOVERY_WAL_STREAM:
+			event_name = "RecoveryWalStream";
+			break;
+		case WAIT_EVENT_SYSLOGGER_MAIN:
+			event_name = "SysLoggerMain";
+			break;
+		case WAIT_EVENT_WAL_RECEIVER_MAIN:
+			event_name = "WalReceiverMain";
+			break;
+		case WAIT_EVENT_WAL_SENDER_MAIN:
+			event_name = "WalSenderMain";
+			break;
+		case WAIT_EVENT_WAL_WRITER_MAIN:
+			event_name = "WalWriterMain";
+			break;
+			/* no default case, so that compiler will warn */
+	}
+
+	return event_name;
+}
+
+/* ----------
+ * pgstat_get_wait_client() -
+ *
+ * Convert WaitEventClient to string.
+ * ----------
+ */
+static const char *
+pgstat_get_wait_client(WaitEventClient w)
+{
+	const char *event_name = "unknown wait event";
+
+	switch (w)
+	{
+		case WAIT_EVENT_CLIENT_READ:
+			event_name = "ClientRead";
+			break;
+		case WAIT_EVENT_CLIENT_WRITE:
+			event_name = "ClientWrite";
+			break;
+		case WAIT_EVENT_GSS_OPEN_SERVER:
+			event_name = "GSSOpenServer";
+			break;
+		case WAIT_EVENT_LIBPQWALRECEIVER_CONNECT:
+			event_name = "LibPQWalReceiverConnect";
+			break;
+		case WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE:
+			event_name = "LibPQWalReceiverReceive";
+			break;
+		case WAIT_EVENT_SSL_OPEN_SERVER:
+			event_name = "SSLOpenServer";
+			break;
+		case WAIT_EVENT_WAL_SENDER_WAIT_WAL:
+			event_name = "WalSenderWaitForWAL";
+			break;
+		case WAIT_EVENT_WAL_SENDER_WRITE_DATA:
+			event_name = "WalSenderWriteData";
+			break;
+			/* no default case, so that compiler will warn */
+	}
+
+	return event_name;
+}
+
+/* ----------
+ * pgstat_get_wait_ipc() -
+ *
+ * Convert WaitEventIPC to string.
+ * ----------
+ */
+static const char *
+pgstat_get_wait_ipc(WaitEventIPC w)
+{
+	const char *event_name = "unknown wait event";
+
+	switch (w)
+	{
+		case WAIT_EVENT_APPEND_READY:
+			event_name = "AppendReady";
+			break;
+		case WAIT_EVENT_BACKUP_WAIT_WAL_ARCHIVE:
+			event_name = "BackupWaitWalArchive";
+			break;
+		case WAIT_EVENT_BGWORKER_SHUTDOWN:
+			event_name = "BgWorkerShutdown";
+			break;
+		case WAIT_EVENT_BGWORKER_STARTUP:
+			event_name = "BgWorkerStartup";
+			break;
+		case WAIT_EVENT_BTREE_PAGE:
+			event_name = "BtreePage";
+			break;
+		case WAIT_EVENT_BUFFER_IO:
+			event_name = "BufferIO";
+			break;
+		case WAIT_EVENT_CHECKPOINT_DONE:
+			event_name = "CheckpointDone";
+			break;
+		case WAIT_EVENT_CHECKPOINT_START:
+			event_name = "CheckpointStart";
+			break;
+		case WAIT_EVENT_EXECUTE_GATHER:
+			event_name = "ExecuteGather";
+			break;
+		case WAIT_EVENT_HASH_BATCH_ALLOCATE:
+			event_name = "HashBatchAllocate";
+			break;
+		case WAIT_EVENT_HASH_BATCH_ELECT:
+			event_name = "HashBatchElect";
+			break;
+		case WAIT_EVENT_HASH_BATCH_LOAD:
+			event_name = "HashBatchLoad";
+			break;
+		case WAIT_EVENT_HASH_BUILD_ALLOCATE:
+			event_name = "HashBuildAllocate";
+			break;
+		case WAIT_EVENT_HASH_BUILD_ELECT:
+			event_name = "HashBuildElect";
+			break;
+		case WAIT_EVENT_HASH_BUILD_HASH_INNER:
+			event_name = "HashBuildHashInner";
+			break;
+		case WAIT_EVENT_HASH_BUILD_HASH_OUTER:
+			event_name = "HashBuildHashOuter";
+			break;
+		case WAIT_EVENT_HASH_GROW_BATCHES_ALLOCATE:
+			event_name = "HashGrowBatchesAllocate";
+			break;
+		case WAIT_EVENT_HASH_GROW_BATCHES_DECIDE:
+			event_name = "HashGrowBatchesDecide";
+			break;
+		case WAIT_EVENT_HASH_GROW_BATCHES_ELECT:
+			event_name = "HashGrowBatchesElect";
+			break;
+		case WAIT_EVENT_HASH_GROW_BATCHES_FINISH:
+			event_name = "HashGrowBatchesFinish";
+			break;
+		case WAIT_EVENT_HASH_GROW_BATCHES_REPARTITION:
+			event_name = "HashGrowBatchesRepartition";
+			break;
+		case WAIT_EVENT_HASH_GROW_BUCKETS_ALLOCATE:
+			event_name = "HashGrowBucketsAllocate";
+			break;
+		case WAIT_EVENT_HASH_GROW_BUCKETS_ELECT:
+			event_name = "HashGrowBucketsElect";
+			break;
+		case WAIT_EVENT_HASH_GROW_BUCKETS_REINSERT:
+			event_name = "HashGrowBucketsReinsert";
+			break;
+		case WAIT_EVENT_LOGICAL_SYNC_DATA:
+			event_name = "LogicalSyncData";
+			break;
+		case WAIT_EVENT_LOGICAL_SYNC_STATE_CHANGE:
+			event_name = "LogicalSyncStateChange";
+			break;
+		case WAIT_EVENT_MQ_INTERNAL:
+			event_name = "MessageQueueInternal";
+			break;
+		case WAIT_EVENT_MQ_PUT_MESSAGE:
+			event_name = "MessageQueuePutMessage";
+			break;
+		case WAIT_EVENT_MQ_RECEIVE:
+			event_name = "MessageQueueReceive";
+			break;
+		case WAIT_EVENT_MQ_SEND:
+			event_name = "MessageQueueSend";
+			break;
+		case WAIT_EVENT_PARALLEL_BITMAP_SCAN:
+			event_name = "ParallelBitmapScan";
+			break;
+		case WAIT_EVENT_PARALLEL_CREATE_INDEX_SCAN:
+			event_name = "ParallelCreateIndexScan";
+			break;
+		case WAIT_EVENT_PARALLEL_FINISH:
+			event_name = "ParallelFinish";
+			break;
+		case WAIT_EVENT_PROCARRAY_GROUP_UPDATE:
+			event_name = "ProcArrayGroupUpdate";
+			break;
+		case WAIT_EVENT_PROC_SIGNAL_BARRIER:
+			event_name = "ProcSignalBarrier";
+			break;
+		case WAIT_EVENT_PROMOTE:
+			event_name = "Promote";
+			break;
+		case WAIT_EVENT_RECOVERY_CONFLICT_SNAPSHOT:
+			event_name = "RecoveryConflictSnapshot";
+			break;
+		case WAIT_EVENT_RECOVERY_CONFLICT_TABLESPACE:
+			event_name = "RecoveryConflictTablespace";
+			break;
+		case WAIT_EVENT_RECOVERY_PAUSE:
+			event_name = "RecoveryPause";
+			break;
+		case WAIT_EVENT_REPLICATION_ORIGIN_DROP:
+			event_name = "ReplicationOriginDrop";
+			break;
+		case WAIT_EVENT_REPLICATION_SLOT_DROP:
+			event_name = "ReplicationSlotDrop";
+			break;
+		case WAIT_EVENT_SAFE_SNAPSHOT:
+			event_name = "SafeSnapshot";
+			break;
+		case WAIT_EVENT_SYNC_REP:
+			event_name = "SyncRep";
+			break;
+		case WAIT_EVENT_WAL_RECEIVER_EXIT:
+			event_name = "WalReceiverExit";
+			break;
+		case WAIT_EVENT_WAL_RECEIVER_WAIT_START:
+			event_name = "WalReceiverWaitStart";
+			break;
+		case WAIT_EVENT_XACT_GROUP_UPDATE:
+			event_name = "XactGroupUpdate";
+			break;
+			/* no default case, so that compiler will warn */
+	}
+
+	return event_name;
+}
+
+/* ----------
+ * pgstat_get_wait_timeout() -
+ *
+ * Convert WaitEventTimeout to string.
+ * ----------
+ */
+static const char *
+pgstat_get_wait_timeout(WaitEventTimeout w)
+{
+	const char *event_name = "unknown wait event";
+
+	switch (w)
+	{
+		case WAIT_EVENT_BASE_BACKUP_THROTTLE:
+			event_name = "BaseBackupThrottle";
+			break;
+		case WAIT_EVENT_PG_SLEEP:
+			event_name = "PgSleep";
+			break;
+		case WAIT_EVENT_RECOVERY_APPLY_DELAY:
+			event_name = "RecoveryApplyDelay";
+			break;
+		case WAIT_EVENT_RECOVERY_RETRIEVE_RETRY_INTERVAL:
+			event_name = "RecoveryRetrieveRetryInterval";
+			break;
+		case WAIT_EVENT_VACUUM_DELAY:
+			event_name = "VacuumDelay";
+			break;
+			/* no default case, so that compiler will warn */
+	}
+
+	return event_name;
+}
+
+/* ----------
+ * pgstat_get_wait_io() -
+ *
+ * Convert WaitEventIO to string.
+ * ----------
+ */
+static const char *
+pgstat_get_wait_io(WaitEventIO w)
+{
+	const char *event_name = "unknown wait event";
+
+	switch (w)
+	{
+		case WAIT_EVENT_BASEBACKUP_READ:
+			event_name = "BaseBackupRead";
+			break;
+		case WAIT_EVENT_BUFFILE_READ:
+			event_name = "BufFileRead";
+			break;
+		case WAIT_EVENT_BUFFILE_WRITE:
+			event_name = "BufFileWrite";
+			break;
+		case WAIT_EVENT_BUFFILE_TRUNCATE:
+			event_name = "BufFileTruncate";
+			break;
+		case WAIT_EVENT_CONTROL_FILE_READ:
+			event_name = "ControlFileRead";
+			break;
+		case WAIT_EVENT_CONTROL_FILE_SYNC:
+			event_name = "ControlFileSync";
+			break;
+		case WAIT_EVENT_CONTROL_FILE_SYNC_UPDATE:
+			event_name = "ControlFileSyncUpdate";
+			break;
+		case WAIT_EVENT_CONTROL_FILE_WRITE:
+			event_name = "ControlFileWrite";
+			break;
+		case WAIT_EVENT_CONTROL_FILE_WRITE_UPDATE:
+			event_name = "ControlFileWriteUpdate";
+			break;
+		case WAIT_EVENT_COPY_FILE_READ:
+			event_name = "CopyFileRead";
+			break;
+		case WAIT_EVENT_COPY_FILE_WRITE:
+			event_name = "CopyFileWrite";
+			break;
+		case WAIT_EVENT_DATA_FILE_EXTEND:
+			event_name = "DataFileExtend";
+			break;
+		case WAIT_EVENT_DATA_FILE_FLUSH:
+			event_name = "DataFileFlush";
+			break;
+		case WAIT_EVENT_DATA_FILE_IMMEDIATE_SYNC:
+			event_name = "DataFileImmediateSync";
+			break;
+		case WAIT_EVENT_DATA_FILE_PREFETCH:
+			event_name = "DataFilePrefetch";
+			break;
+		case WAIT_EVENT_DATA_FILE_READ:
+			event_name = "DataFileRead";
+			break;
+		case WAIT_EVENT_DATA_FILE_SYNC:
+			event_name = "DataFileSync";
+			break;
+		case WAIT_EVENT_DATA_FILE_TRUNCATE:
+			event_name = "DataFileTruncate";
+			break;
+		case WAIT_EVENT_DATA_FILE_WRITE:
+			event_name = "DataFileWrite";
+			break;
+		case WAIT_EVENT_DSM_FILL_ZERO_WRITE:
+			event_name = "DSMFillZeroWrite";
+			break;
+		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_READ:
+			event_name = "LockFileAddToDataDirRead";
+			break;
+		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_SYNC:
+			event_name = "LockFileAddToDataDirSync";
+			break;
+		case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_WRITE:
+			event_name = "LockFileAddToDataDirWrite";
+			break;
+		case WAIT_EVENT_LOCK_FILE_CREATE_READ:
+			event_name = "LockFileCreateRead";
+			break;
+		case WAIT_EVENT_LOCK_FILE_CREATE_SYNC:
+			event_name = "LockFileCreateSync";
+			break;
+		case WAIT_EVENT_LOCK_FILE_CREATE_WRITE:
+			event_name = "LockFileCreateWrite";
+			break;
+		case WAIT_EVENT_LOCK_FILE_RECHECKDATADIR_READ:
+			event_name = "LockFileReCheckDataDirRead";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_CHECKPOINT_SYNC:
+			event_name = "LogicalRewriteCheckpointSync";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_SYNC:
+			event_name = "LogicalRewriteMappingSync";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_WRITE:
+			event_name = "LogicalRewriteMappingWrite";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_SYNC:
+			event_name = "LogicalRewriteSync";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_TRUNCATE:
+			event_name = "LogicalRewriteTruncate";
+			break;
+		case WAIT_EVENT_LOGICAL_REWRITE_WRITE:
+			event_name = "LogicalRewriteWrite";
+			break;
+		case WAIT_EVENT_RELATION_MAP_READ:
+			event_name = "RelationMapRead";
+			break;
+		case WAIT_EVENT_RELATION_MAP_SYNC:
+			event_name = "RelationMapSync";
+			break;
+		case WAIT_EVENT_RELATION_MAP_WRITE:
+			event_name = "RelationMapWrite";
+			break;
+		case WAIT_EVENT_REORDER_BUFFER_READ:
+			event_name = "ReorderBufferRead";
+			break;
+		case WAIT_EVENT_REORDER_BUFFER_WRITE:
+			event_name = "ReorderBufferWrite";
+			break;
+		case WAIT_EVENT_REORDER_LOGICAL_MAPPING_READ:
+			event_name = "ReorderLogicalMappingRead";
+			break;
+		case WAIT_EVENT_REPLICATION_SLOT_READ:
+			event_name = "ReplicationSlotRead";
+			break;
+		case WAIT_EVENT_REPLICATION_SLOT_RESTORE_SYNC:
+			event_name = "ReplicationSlotRestoreSync";
+			break;
+		case WAIT_EVENT_REPLICATION_SLOT_SYNC:
+			event_name = "ReplicationSlotSync";
+			break;
+		case WAIT_EVENT_REPLICATION_SLOT_WRITE:
+			event_name = "ReplicationSlotWrite";
+			break;
+		case WAIT_EVENT_SLRU_FLUSH_SYNC:
+			event_name = "SLRUFlushSync";
+			break;
+		case WAIT_EVENT_SLRU_READ:
+			event_name = "SLRURead";
+			break;
+		case WAIT_EVENT_SLRU_SYNC:
+			event_name = "SLRUSync";
+			break;
+		case WAIT_EVENT_SLRU_WRITE:
+			event_name = "SLRUWrite";
+			break;
+		case WAIT_EVENT_SNAPBUILD_READ:
+			event_name = "SnapbuildRead";
+			break;
+		case WAIT_EVENT_SNAPBUILD_SYNC:
+			event_name = "SnapbuildSync";
+			break;
+		case WAIT_EVENT_SNAPBUILD_WRITE:
+			event_name = "SnapbuildWrite";
+			break;
+		case WAIT_EVENT_TIMELINE_HISTORY_FILE_SYNC:
+			event_name = "TimelineHistoryFileSync";
+			break;
+		case WAIT_EVENT_TIMELINE_HISTORY_FILE_WRITE:
+			event_name = "TimelineHistoryFileWrite";
+			break;
+		case WAIT_EVENT_TIMELINE_HISTORY_READ:
+			event_name = "TimelineHistoryRead";
+			break;
+		case WAIT_EVENT_TIMELINE_HISTORY_SYNC:
+			event_name = "TimelineHistorySync";
+			break;
+		case WAIT_EVENT_TIMELINE_HISTORY_WRITE:
+			event_name = "TimelineHistoryWrite";
+			break;
+		case WAIT_EVENT_TWOPHASE_FILE_READ:
+			event_name = "TwophaseFileRead";
+			break;
+		case WAIT_EVENT_TWOPHASE_FILE_SYNC:
+			event_name = "TwophaseFileSync";
+			break;
+		case WAIT_EVENT_TWOPHASE_FILE_WRITE:
+			event_name = "TwophaseFileWrite";
+			break;
+		case WAIT_EVENT_WALSENDER_TIMELINE_HISTORY_READ:
+			event_name = "WALSenderTimelineHistoryRead";
+			break;
+		case WAIT_EVENT_WAL_BOOTSTRAP_SYNC:
+			event_name = "WALBootstrapSync";
+			break;
+		case WAIT_EVENT_WAL_BOOTSTRAP_WRITE:
+			event_name = "WALBootstrapWrite";
+			break;
+		case WAIT_EVENT_WAL_COPY_READ:
+			event_name = "WALCopyRead";
+			break;
+		case WAIT_EVENT_WAL_COPY_SYNC:
+			event_name = "WALCopySync";
+			break;
+		case WAIT_EVENT_WAL_COPY_WRITE:
+			event_name = "WALCopyWrite";
+			break;
+		case WAIT_EVENT_WAL_INIT_SYNC:
+			event_name = "WALInitSync";
+			break;
+		case WAIT_EVENT_WAL_INIT_WRITE:
+			event_name = "WALInitWrite";
+			break;
+		case WAIT_EVENT_WAL_READ:
+			event_name = "WALRead";
+			break;
+		case WAIT_EVENT_WAL_SYNC:
+			event_name = "WALSync";
+			break;
+		case WAIT_EVENT_WAL_SYNC_METHOD_ASSIGN:
+			event_name = "WALSyncMethodAssign";
+			break;
+		case WAIT_EVENT_WAL_WRITE:
+			event_name = "WALWrite";
+			break;
+		case WAIT_EVENT_LOGICAL_CHANGES_READ:
+			event_name = "LogicalChangesRead";
+			break;
+		case WAIT_EVENT_LOGICAL_CHANGES_WRITE:
+			event_name = "LogicalChangesWrite";
+			break;
+		case WAIT_EVENT_LOGICAL_SUBXACT_READ:
+			event_name = "LogicalSubxactRead";
+			break;
+		case WAIT_EVENT_LOGICAL_SUBXACT_WRITE:
+			event_name = "LogicalSubxactWrite";
+			break;
+
+			/* no default case, so that compiler will warn */
+	}
+
+	return event_name;
+}