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

Commit8b4efe1

Browse files
committed
Protect against torn pages when deleting GIN list pages.
To-be-deleted list pages contain no useful information, as they are beingdeleted, but we must still protect the writes from being torn by a crashafter a partial write. To do that, re-initialize the pages on WAL replay.Jeff Janes caught this with a test program to test partial writes.Backpatch to all supported versions.
1 parent77e6628 commit8b4efe1

File tree

1 file changed

+14
-14
lines changed

1 file changed

+14
-14
lines changed

‎src/backend/access/gin/ginxlog.c

Lines changed: 14 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -698,26 +698,26 @@ ginRedoDeleteListPages(XLogRecPtr lsn, XLogRecord *record)
698698
* cannot get past a reader that is on, or due to visit, any page we are
699699
* going to delete. New incoming readers will block behind our metapage
700700
* lock and then see a fully updated page list.
701+
*
702+
* No full-page images are taken of the deleted pages. Instead, they are
703+
* re-initialized as empty, deleted pages. Their right-links don't need to
704+
* be preserved, because no new readers can see the pages, as explained
705+
* above.
701706
*/
702707
for (i=0;i<data->ndeleted;i++)
703708
{
704-
Bufferbuffer=XLogReadBuffer(data->node,data->toDelete[i], false);
709+
Bufferbuffer;
710+
Pagepage;
705711

706-
if (BufferIsValid(buffer))
707-
{
708-
Pagepage=BufferGetPage(buffer);
709-
710-
if (!XLByteLE(lsn,PageGetLSN(page)))
711-
{
712-
GinPageGetOpaque(page)->flags=GIN_DELETED;
712+
buffer=XLogReadBuffer(data->node,data->toDelete[i], true);
713+
page=BufferGetPage(buffer);
714+
GinInitBuffer(buffer,GIN_DELETED);
713715

714-
PageSetLSN(page,lsn);
715-
PageSetTLI(page,ThisTimeLineID);
716-
MarkBufferDirty(buffer);
717-
}
716+
PageSetLSN(page,lsn);
717+
PageSetTLI(page,ThisTimeLineID);
718+
MarkBufferDirty(buffer);
718719

719-
UnlockReleaseBuffer(buffer);
720-
}
720+
UnlockReleaseBuffer(buffer);
721721
}
722722
UnlockReleaseBuffer(metabuffer);
723723
}

0 commit comments

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