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Replace XLogRecPtr struct with a 64-bit integer.

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This simplifies code that needs to do arithmetic on XLogRecPtrs.

To avoid changing on-disk format of data pages, the LSN on data pages is
still stored in the old format. That should keep pg_upgrade happy. However,
we have XLogRecPtrs embedded in the control file, and in the structs that
are sent over the replication protocol, so this changes breaks compatibility
of pg_basebackup and server. I didn't do anything about this in this patch,
per discussion on -hackers, the right thing to do would to be to change the
replication protocol to be architecture-independent, so that you could use
a newer version of pg_receivexlog, for example, against an older server
version.
This commit is contained in:
Heikki Linnakangas
2012-06-24 18:51:37 +03:00
parent 061e7efb1b
commit 0ab9d1c4b3
28 changed files with 279 additions and 357 deletions
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35
src/include/access/xlog_internal.h
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@@ -51,7 +51,7 @@ typedef struct BkpBlock
/*
* Each page of XLOG file has a header like this:
*/
#define XLOG_PAGE_MAGIC 0xD074 /* can be used as WAL version indicator */
#define XLOG_PAGE_MAGIC 0xD075 /* can be used as WAL version indicator */
typedef struct XLogPageHeaderData
{
@@ -113,10 +113,7 @@ typedef XLogLongPageHeaderData *XLogLongPageHeader;
#define XLogSegmentsPerXLogId (0x100000000L / XLOG_SEG_SIZE)
#define XLogSegNoOffsetToRecPtr(segno, offset, dest) \
do { \
(dest).xlogid = (segno) / XLogSegmentsPerXLogId; \
(dest).xrecoff = ((segno) % XLogSegmentsPerXLogId) * XLOG_SEG_SIZE + (offset); \
} while (0)
(dest) = (segno) * XLOG_SEG_SIZE + (offset)
/*
* Macros for manipulating XLOG pointers
@@ -125,8 +122,8 @@ typedef XLogLongPageHeaderData *XLogLongPageHeader;
/* Align a record pointer to next page */
#define NextLogPage(recptr) \
do { \
if ((recptr).xrecoff % XLOG_BLCKSZ != 0) \
XLByteAdvance(recptr, (XLOG_BLCKSZ - (recptr).xrecoff % XLOG_BLCKSZ)); \
if ((recptr) % XLOG_BLCKSZ != 0) \
XLByteAdvance(recptr, (XLOG_BLCKSZ - (recptr) % XLOG_BLCKSZ)); \
} while (0)
/*
@@ -135,14 +132,13 @@ typedef XLogLongPageHeaderData *XLogLongPageHeader;
* For XLByteToSeg, do the computation at face value. For XLByteToPrevSeg,
* a boundary byte is taken to be in the previous segment. This is suitable
* for deciding which segment to write given a pointer to a record end,
* for example. (We can assume xrecoff is not zero, since no valid recptr
* can have that.)
* for example.
*/
#define XLByteToSeg(xlrp, logSegNo) \
logSegNo = ((uint64) (xlrp).xlogid * XLogSegmentsPerXLogId) + (xlrp).xrecoff / XLogSegSize
logSegNo = (xlrp) / XLogSegSize
#define XLByteToPrevSeg(xlrp, logSegNo) \
logSegNo = ((uint64) (xlrp).xlogid * XLogSegmentsPerXLogId) + ((xlrp).xrecoff - 1) / XLogSegSize
logSegNo = ((xlrp) - 1) / XLogSegSize
/*
* Is an XLogRecPtr within a particular XLOG segment?
@@ -151,20 +147,15 @@ typedef XLogLongPageHeaderData *XLogLongPageHeader;
* a boundary byte is taken to be in the previous segment.
*/
#define XLByteInSeg(xlrp, logSegNo) \
(((xlrp).xlogid) == (logSegNo) / XLogSegmentsPerXLogId && \
((xlrp).xrecoff / XLogSegSize) == (logSegNo) % XLogSegmentsPerXLogId)
(((xlrp) / XLogSegSize) == (logSegNo))
#define XLByteInPrevSeg(xlrp, logSegNo) \
(((xlrp).xrecoff == 0) ? \
(((xlrp).xlogid - 1) == (logSegNo) / XLogSegmentsPerXLogId && \
((uint32) 0xffffffff) / XLogSegSize == (logSegNo) % XLogSegmentsPerXLogId) : \
((xlrp).xlogid) == (logSegNo) / XLogSegmentsPerXLogId && \
(((xlrp).xrecoff - 1) / XLogSegSize) == (logSegNo) % XLogSegmentsPerXLogId)
((((xlrp) - 1) / XLogSegSize) == (logSegNo))
/* Check if an xrecoff value is in a plausible range */
#define XRecOffIsValid(xrecoff) \
((xrecoff) % XLOG_BLCKSZ >= SizeOfXLogShortPHD && \
(XLOG_BLCKSZ - (xrecoff) % XLOG_BLCKSZ) >= SizeOfXLogRecord)
/* Check if an XLogRecPtr value is in a plausible range */
#define XRecOffIsValid(xlrp) \
((xlrp) % XLOG_BLCKSZ >= SizeOfXLogShortPHD && \
(XLOG_BLCKSZ - (xlrp) % XLOG_BLCKSZ) >= SizeOfXLogRecord)
/*
* The XLog directory and control file (relative to $PGDATA)