NotificationsYou must be signed in to change notification settings
Fork28
Star151

Commitd67dae0

committed

Don't count zero-filled buffers as 'read' in EXPLAIN.

If you extend a relation, it should count as a block written, notread (we write a zero-filled block). If you ask for a zero-filledbuffer, it shouldn't be counted as read or written.Later we might consider counting zero-filled buffers with a separatecounter, if they become more common due to future work.Author: Thomas MunroReviewed-by: Haribabu Kommi, Kyotaro Horiguchi, David RowleyDiscussion:https://postgr.es/m/CAEepm%3D3JytB3KPpvSwXzkY%2Bdwc5zC8P8Lk7Nedkoci81_0E9rA%40mail.gmail.com

1 parent471a7af commitd67dae0Copy full SHA for d67dae0

File tree

1 file changed

-2

lines changed

src/backend/storage/buffer
- bufmgr.c

1 file changed

-2

lines changed

`‎src/backend/storage/buffer/bufmgr.c`

Lines changed: 8 additions & 2 deletions

Original file line number	Diff line number	Diff line change
`@@ -733,7 +733,10 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,`
`733`	`733`	`bufHdr=LocalBufferAlloc(smgr,forkNum,blockNum,&found);`
`734`	`734`	`if (found)`
`735`	`735`	`pgBufferUsage.local_blks_hit++;`
`736`		`-else`
	`736`	`+elseif (isExtend)`
	`737`	`+pgBufferUsage.local_blks_written++;`
	`738`	`+elseif (mode==RBM_NORMAL\|\|mode==RBM_NORMAL_NO_LOG\|\|`
	`739`	`+mode==RBM_ZERO_ON_ERROR)`
`737`	`740`	`pgBufferUsage.local_blks_read++;`
`738`	`741`	`}`
`739`	`742`	`else`
`@@ -746,7 +749,10 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,`
`746`	`749`	`strategy,&found);`
`747`	`750`	`if (found)`
`748`	`751`	`pgBufferUsage.shared_blks_hit++;`
`749`		`-else`
	`752`	`+elseif (isExtend)`
	`753`	`+pgBufferUsage.shared_blks_written++;`
	`754`	`+elseif (mode==RBM_NORMAL\|\|mode==RBM_NORMAL_NO_LOG\|\|`
	`755`	`+mode==RBM_ZERO_ON_ERROR)`
`750`	`756`	`pgBufferUsage.shared_blks_read++;`
`751`	`757`	`}`
`752`	`758`

0 commit comments

Comments

(0)

Movatterモバイル変換

Navigation Menu

Search code, repositories, users, issues, pull requests...

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Commitd67dae0

File tree

1 file changed

1 file changed

`‎src/backend/storage/buffer/bufmgr.c`

0 commit comments