Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

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

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit0ea71c9

Browse files
Notice that heap page has dead items during VACUUM.
Consistently set a flag variable that tracks whether the current heappage has a dead item during lazy vacuum's heap scan. We missed thecommon case where there is an preexisting (or even a new) LP_DEAD heapline pointer.Also make it clear that the variable might be affected by an existingline pointer, say from an earlier opportunistic pruning operation. Thisdistinction is important because it's the main reason why we can't justuse the nearby tups_vacuumed variable instead.No backpatch. In theory failing to set the page level flag variable hadno consequences. Currently it is only used to defensively check if apage marked all visible has dead items, which should never happen anyway(if it does then the table must be corrupt).Author: Masahiko Sawada <sawada.mshk@gmail.com>Diagnosed-By: Masahiko Sawada <sawada.mshk@gmail.com>Discussion:https://postgr.es/m/CAD21AoAtZb4+HJT_8RoOXvu4HM-Zd4HKS3YSMCH6+-W=bDyh-w@mail.gmail.com
1 parent58f5749 commit0ea71c9

File tree

1 file changed

+6
-5
lines changed

1 file changed

+6
-5
lines changed

‎src/backend/access/heap/vacuumlazy.c

Lines changed: 6 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -945,7 +945,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
945945
boolall_visible_according_to_vm= false;
946946
boolall_visible;
947947
boolall_frozen= true;/* provided all_visible is also true */
948-
boolhas_dead_tuples;
948+
boolhas_dead_items;/* includes existing LP_DEAD items */
949949
TransactionIdvisibility_cutoff_xid=InvalidTransactionId;
950950

951951
/* see note above about forcing scanning of last page */
@@ -1248,7 +1248,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
12481248
* requiring freezing.
12491249
*/
12501250
all_visible= true;
1251-
has_dead_tuples= false;
1251+
has_dead_items= false;
12521252
nfrozen=0;
12531253
hastup= false;
12541254
prev_dead_count=dead_tuples->num_tuples;
@@ -1300,6 +1300,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
13001300
{
13011301
lazy_record_dead_tuple(dead_tuples,&(tuple.t_self));
13021302
all_visible= false;
1303+
has_dead_items= true;
13031304
continue;
13041305
}
13051306

@@ -1448,7 +1449,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
14481449
HeapTupleHeaderAdvanceLatestRemovedXid(tuple.t_data,
14491450
&vacrelstats->latestRemovedXid);
14501451
tups_vacuumed+=1;
1451-
has_dead_tuples= true;
1452+
has_dead_items= true;
14521453
}
14531454
else
14541455
{
@@ -1527,7 +1528,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
15271528
/* Remove tuples from heap if the table has no index */
15281529
lazy_vacuum_page(onerel,blkno,buf,0,vacrelstats,&vmbuffer);
15291530
vacuumed_pages++;
1530-
has_dead_tuples= false;
1531+
has_dead_items= false;
15311532
}
15321533
else
15331534
{
@@ -1625,7 +1626,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
16251626
* There should never be dead tuples on a page with PD_ALL_VISIBLE
16261627
* set, however.
16271628
*/
1628-
elseif (PageIsAllVisible(page)&&has_dead_tuples)
1629+
elseif (PageIsAllVisible(page)&&has_dead_items)
16291630
{
16301631
elog(WARNING,"page containing dead tuples is marked as all-visible in relation \"%s\" page %u",
16311632
vacrelstats->relname,blkno);

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp