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PostgreSQL 10 support.

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This commit is contained in:
David Steele
2017-09-01 12:29:34 -04:00
parent 36e576b483
commit fcb7c6fd1d
26 changed files with 359 additions and 254 deletions
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14
src/postgres/pageChecksum.c
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@ -71,18 +71,18 @@ For historical reasons, the 64-bit LSN value is stored as two 32-bit values.
***********************************************************************************************************************************/
typedef struct
{
uint32 xlogid; /* high bits */
uint32 walid; /* high bits */
uint32 xrecoff; /* low bits */
} PageXLogRecPtr;
} PageWalRecPtr;
/***********************************************************************************************************************************
Space management information generic to any page. Only values required for pgBackRest are represented here.
pd_lsn - identifies xlog record for last change to this page.
pd_lsn - identifies wal record for last change to this page.
pd_checksum - page checksum, if set.
The LSN is used by the buffer manager to enforce the basic rule of WAL: "thou shalt write xlog before data". A dirty buffer cannot
be dumped to disk until xlog has been flushed at least as far as the page's LSN.
The LSN is used by the buffer manager to enforce the basic rule of WAL: "thou shalt write wal before data". A dirty buffer cannot
be dumped to disk until wal has been flushed at least as far as the page's LSN.
pd_checksum stores the page checksum, if it has been set for this page; zero is a valid value for a checksum. If a checksum is not
in use then we leave the field unset. This will typically mean the field is zero though non-zero values may also be present if
@ -94,7 +94,7 @@ relating to checksums.
typedef struct PageHeaderData
{
// LSN is member of *any* block, not only page-organized ones
PageXLogRecPtr pd_lsn; /* LSN: next byte after last byte of xlog * record for last change to this page */
PageWalRecPtr pd_lsn; /* LSN: next byte after last byte of wal * record for last change to this page */
uint16 pd_checksum; /* checksum */
uint16 pd_flags; /* flag bits, see below */
uint16 pd_lower; /* offset to start of free space */
@ -197,7 +197,7 @@ pageChecksumTest(const char *szPage, uint32 uiBlockNo, uint32 uiPageSize, uint32
// This is a new page so don't test checksum
((PageHeader)szPage)->pd_upper == 0 ||
// LSN is after the backup started so checksum is not tested because pages may be torn
(((PageHeader)szPage)->pd_lsn.xlogid >= uiIgnoreWalId && ((PageHeader)szPage)->pd_lsn.xrecoff >= uiIgnoreWalOffset) ||
(((PageHeader)szPage)->pd_lsn.walid >= uiIgnoreWalId && ((PageHeader)szPage)->pd_lsn.xrecoff >= uiIgnoreWalOffset) ||
// Checksum is valid
((PageHeader)szPage)->pd_checksum == pageChecksum(szPage, uiBlockNo, uiPageSize);
}