diff options
Diffstat (limited to 'src/backend/storage/page')
| -rw-r--r-- | src/backend/storage/page/README | 3 | ||||
| -rw-r--r-- | src/backend/storage/page/bufpage.c | 6 |
2 files changed, 5 insertions, 4 deletions
diff --git a/src/backend/storage/page/README b/src/backend/storage/page/README index 5127d98da37..f873fb0eea1 100644 --- a/src/backend/storage/page/README +++ b/src/backend/storage/page/README @@ -9,7 +9,8 @@ have a very low measured incidence according to research on large server farms, http://www.cs.toronto.edu/~bianca/papers/sigmetrics09.pdf, discussed 2010/12/22 on -hackers list. -Current implementation requires this be enabled system-wide at initdb time. +Checksums can be enabled at initdb time, but can also be turned on and off +using pg_enable_data_checksums()/pg_disable_data_checksums() at runtime. The checksum is not valid at all times on a data page!! The checksum is valid when the page leaves the shared pool and is checked diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c index dfbda5458fd..790e4b860ad 100644 --- a/src/backend/storage/page/bufpage.c +++ b/src/backend/storage/page/bufpage.c @@ -93,7 +93,7 @@ PageIsVerified(Page page, BlockNumber blkno) */ if (!PageIsNew(page)) { - if (DataChecksumsEnabled()) + if (DataChecksumsNeedVerify()) { checksum = pg_checksum_page((char *) page, blkno); @@ -1168,7 +1168,7 @@ PageSetChecksumCopy(Page page, BlockNumber blkno) static char *pageCopy = NULL; /* If we don't need a checksum, just return the passed-in data */ - if (PageIsNew(page) || !DataChecksumsEnabled()) + if (PageIsNew(page) || !DataChecksumsNeedWrite()) return (char *) page; /* @@ -1195,7 +1195,7 @@ void PageSetChecksumInplace(Page page, BlockNumber blkno) { /* If we don't need a checksum, just return */ - if (PageIsNew(page) || !DataChecksumsEnabled()) + if (PageIsNew(page) || !DataChecksumsNeedWrite()) return; ((PageHeader) page)->pd_checksum = pg_checksum_page((char *) page, blkno); |