Count write times when extending relation files for shared buffers

michaelpq · michaelpq · commit d17ffc734dad · 2023-10-18T14:54:33.000+09:00
Relation files extended by multiple blocks at a time have been counting the number of blocks written, but forgot to increment the write time in this case, as single-block write and relation extension are treated as two different I/O operations in the shared stats: IOOP_EXTEND vs IOOP_WRITE. In this case IOOP_EXTEND was forgotten for normal (non-temporary) relations, still the number of blocks written was incremented according to the relation extend done. Write times are tracked when track_io_timing is enabled, which is not the case by default. Author: Nazir Bilal Yavuz Reviewed-by: Robert Haas, Melanie Plageman Discussion: https://postgr.es/m/CAN55FZ19Ss279mZuqGbuUNxka0iPbLgYuOQXqAKewrjNrp27VA@mail.gmail.com Backpatch-through: 16
diff --git a/src/backend/utils/activity/pgstat_io.c b/src/backend/utils/activity/pgstat_io.c
@@ -119,7 +119,7 @@ pgstat_count_io_op_time(IOObject io_object, IOContext io_context, IOOp io_op,
 		INSTR_TIME_SET_CURRENT(io_time);
 		INSTR_TIME_SUBTRACT(io_time, start_time);
 
-		if (io_op == IOOP_WRITE)
+		if (io_op == IOOP_WRITE || io_op == IOOP_EXTEND)
 		{
 			pgstat_count_buffer_write_time(INSTR_TIME_GET_MICROSEC(io_time));
 			if (io_object == IOOBJECT_RELATION)

Original file line number	Diff line number	Diff line change
`@@ -119,7 +119,7 @@ pgstat_count_io_op_time(IOObject io_object, IOContext io_context, IOOp io_op,`
`119`	`119`	`INSTR_TIME_SET_CURRENT(io_time);`
`120`	`120`	`INSTR_TIME_SUBTRACT(io_time, start_time);`
`121`	`121`
`122`		`- if (io_op == IOOP_WRITE)`
	`122`	`+ if (io_op == IOOP_WRITE \|\| io_op == IOOP_EXTEND)`
`123`	`123`	`{`
`124`	`124`	`pgstat_count_buffer_write_time(INSTR_TIME_GET_MICROSEC(io_time));`
`125`	`125`	`if (io_object == IOOBJECT_RELATION)`