Create and use wait events for read, write, and fsync operations.

Previous commits, notably 53be0b1add7064ca5db3cd884302dfc3268d884e and
6f3bd98ebfc008cbd676da777bb0b2376c4c4bfa, made it possible to see from
pg_stat_activity when a backend was stuck waiting for another backend,
but it's also fairly common for a backend to be stuck waiting for an
I/O.  Add wait events for those operations, too.

Rushabh Lathia, with further hacking by me.  Reviewed and tested by
Michael Paquier, Amit Kapila, Rajkumar Raghuwanshi, and Rahila Syed.

Discussion: http://postgr.es/m/CAGPqQf0LsYHXREPAZqYGVkDqHSyjf=KsD=k0GTVPAuzyThh-VQ@mail.gmail.com

1 files changed, 233 insertions, 0 deletions

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 7cacb1e9b24..5fe9f35199a 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -280,6 +280,7 @@ 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);
@@ -3176,6 +3177,9 @@ pgstat_get_wait_event_type(uint32 wait_event_info)
 		case PG_WAIT_TIMEOUT:
 			event_type = "Timeout";
 			break;
+		case PG_WAIT_IO:
+			event_type = "IO";
+			break;
 		default:
 			event_type = "???";
 			break;
@@ -3246,6 +3250,13 @@ pgstat_get_wait_event(uint32 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;
@@ -3439,6 +3450,228 @@ pgstat_get_wait_timeout(WaitEventTimeout w)
 }
 
 /* ----------
+ * 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_BUFFILE_READ:
+			event_name = "BufFileRead";
+			break;
+		case WAIT_EVENT_BUFFILE_WRITE:
+			event_name = "BufFileWrite";
+			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_METHOD_ASSIGN:
+			event_name = "WALSyncMethodAssign";
+			break;
+		case WAIT_EVENT_WAL_WRITE:
+			event_name = "WALWrite";
+			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