Header And Logo
|
#include "access/xlog.h"
Go to the source code of this file.
Defines | |
| #define | TRANSACTION_STATUS_IN_PROGRESS 0x00 |
| #define | TRANSACTION_STATUS_COMMITTED 0x01 |
| #define | TRANSACTION_STATUS_ABORTED 0x02 |
| #define | TRANSACTION_STATUS_SUB_COMMITTED 0x03 |
| #define | CLOG_ZEROPAGE 0x00 |
| #define | CLOG_TRUNCATE 0x10 |
Typedefs | |
| typedef int | XidStatus |
Functions | |
| void | TransactionIdSetTreeStatus (TransactionId xid, int nsubxids, TransactionId *subxids, XidStatus status, XLogRecPtr lsn) |
| XidStatus | TransactionIdGetStatus (TransactionId xid, XLogRecPtr *lsn) |
| Size | CLOGShmemBuffers (void) |
| Size | CLOGShmemSize (void) |
| void | CLOGShmemInit (void) |
| void | BootStrapCLOG (void) |
| void | StartupCLOG (void) |
| void | TrimCLOG (void) |
| void | ShutdownCLOG (void) |
| void | CheckPointCLOG (void) |
| void | ExtendCLOG (TransactionId newestXact) |
| void | TruncateCLOG (TransactionId oldestXact) |
| void | clog_redo (XLogRecPtr lsn, XLogRecord *record) |
| void | clog_desc (StringInfo buf, uint8 xl_info, char *rec) |
| #define CLOG_TRUNCATE 0x10 |
Definition at line 48 of file clog.h.
Referenced by clog_desc(), clog_redo(), and WriteTruncateXlogRec().
| #define CLOG_ZEROPAGE 0x00 |
Definition at line 47 of file clog.h.
Referenced by clog_desc(), clog_redo(), and WriteZeroPageXlogRec().
| #define TRANSACTION_STATUS_ABORTED 0x02 |
Definition at line 27 of file clog.h.
Referenced by TransactionIdAbortTree(), TransactionIdDidAbort(), TransactionIdSetPageStatus(), and TransactionIdSetTreeStatus().
| #define TRANSACTION_STATUS_COMMITTED 0x01 |
Definition at line 26 of file clog.h.
Referenced by TransactionIdAsyncCommitTree(), TransactionIdCommitTree(), TransactionIdDidCommit(), TransactionIdSetPageStatus(), TransactionIdSetStatusBit(), and TransactionIdSetTreeStatus().
| #define TRANSACTION_STATUS_IN_PROGRESS 0x00 |
Definition at line 25 of file clog.h.
Referenced by TransactionIdSetStatusBit(), and TransactionLogFetch().
| #define TRANSACTION_STATUS_SUB_COMMITTED 0x03 |
Definition at line 28 of file clog.h.
Referenced by TransactionIdDidAbort(), TransactionIdDidCommit(), TransactionIdSetPageStatus(), TransactionIdSetStatusBit(), TransactionIdSetTreeStatus(), and TransactionLogFetch().
| void BootStrapCLOG | ( | void | ) |
Definition at line 467 of file clog.c.
References Assert, CLogControlLock, ClogCtl, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), SimpleLruWritePage(), and ZeroCLOGPage().
Referenced by BootStrapXLOG().
{
int slotno;
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
/* Create and zero the first page of the commit log */
slotno = ZeroCLOGPage(0, false);
/* Make sure it's written out */
SimpleLruWritePage(ClogCtl, slotno);
Assert(!ClogCtl->shared->page_dirty[slotno]);
LWLockRelease(CLogControlLock);
}
| void CheckPointCLOG | ( | void | ) |
Definition at line 590 of file clog.c.
References ClogCtl, and SimpleLruFlush().
Referenced by CheckPointGuts().
{
/* Flush dirty CLOG pages to disk */
TRACE_POSTGRESQL_CLOG_CHECKPOINT_START(true);
SimpleLruFlush(ClogCtl, true);
TRACE_POSTGRESQL_CLOG_CHECKPOINT_DONE(true);
}
| void clog_desc | ( | StringInfo | buf, | |
| uint8 | xl_info, | |||
| char * | rec | |||
| ) |
Definition at line 21 of file clogdesc.c.
References appendStringInfo(), CLOG_TRUNCATE, and CLOG_ZEROPAGE.
{
uint8 info = xl_info & ~XLR_INFO_MASK;
if (info == CLOG_ZEROPAGE)
{
int pageno;
memcpy(&pageno, rec, sizeof(int));
appendStringInfo(buf, "zeropage: %d", pageno);
}
else if (info == CLOG_TRUNCATE)
{
int pageno;
memcpy(&pageno, rec, sizeof(int));
appendStringInfo(buf, "truncate before: %d", pageno);
}
else
appendStringInfo(buf, "UNKNOWN");
}
| void clog_redo | ( | XLogRecPtr | lsn, | |
| XLogRecord * | record | |||
| ) |
Definition at line 732 of file clog.c.
References Assert, CLOG_TRUNCATE, CLOG_ZEROPAGE, CLogControlLock, ClogCtl, elog, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), PANIC, SimpleLruTruncate(), SimpleLruWritePage(), XLogRecord::xl_info, XLogRecGetData, XLR_BKP_BLOCK_MASK, and ZeroCLOGPage().
{
uint8 info = record->xl_info & ~XLR_INFO_MASK;
/* Backup blocks are not used in clog records */
Assert(!(record->xl_info & XLR_BKP_BLOCK_MASK));
if (info == CLOG_ZEROPAGE)
{
int pageno;
int slotno;
memcpy(&pageno, XLogRecGetData(record), sizeof(int));
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
slotno = ZeroCLOGPage(pageno, false);
SimpleLruWritePage(ClogCtl, slotno);
Assert(!ClogCtl->shared->page_dirty[slotno]);
LWLockRelease(CLogControlLock);
}
else if (info == CLOG_TRUNCATE)
{
int pageno;
memcpy(&pageno, XLogRecGetData(record), sizeof(int));
/*
* During XLOG replay, latest_page_number isn't set up yet; insert a
* suitable value to bypass the sanity test in SimpleLruTruncate.
*/
ClogCtl->shared->latest_page_number = pageno;
SimpleLruTruncate(ClogCtl, pageno);
}
else
elog(PANIC, "clog_redo: unknown op code %u", info);
}
| Size CLOGShmemBuffers | ( | void | ) |
Definition at line 438 of file clog.c.
References Max, Min, and NBuffers.
Referenced by CLOGShmemInit(), CLOGShmemSize(), and NumLWLocks().
| void CLOGShmemInit | ( | void | ) |
Definition at line 453 of file clog.c.
References CLOG_LSNS_PER_PAGE, CLogControlLock, ClogCtl, CLOGShmemBuffers(), and SimpleLruInit().
Referenced by CreateSharedMemoryAndSemaphores().
{
ClogCtl->PagePrecedes = CLOGPagePrecedes;
SimpleLruInit(ClogCtl, "CLOG Ctl", CLOGShmemBuffers(), CLOG_LSNS_PER_PAGE,
CLogControlLock, "pg_clog");
}
| Size CLOGShmemSize | ( | void | ) |
Definition at line 447 of file clog.c.
References CLOG_LSNS_PER_PAGE, CLOGShmemBuffers(), and SimpleLruShmemSize().
Referenced by CreateSharedMemoryAndSemaphores().
{
return SimpleLruShmemSize(CLOGShmemBuffers(), CLOG_LSNS_PER_PAGE);
}
| void ExtendCLOG | ( | TransactionId | newestXact | ) |
Definition at line 608 of file clog.c.
References CLogControlLock, FirstNormalTransactionId, InRecovery, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), TransactionIdEquals, TransactionIdToPage, TransactionIdToPgIndex, and ZeroCLOGPage().
Referenced by GetNewTransactionId(), and RecordKnownAssignedTransactionIds().
{
int pageno;
/*
* No work except at first XID of a page. But beware: just after
* wraparound, the first XID of page zero is FirstNormalTransactionId.
*/
if (TransactionIdToPgIndex(newestXact) != 0 &&
!TransactionIdEquals(newestXact, FirstNormalTransactionId))
return;
pageno = TransactionIdToPage(newestXact);
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
/* Zero the page and make an XLOG entry about it */
ZeroCLOGPage(pageno, !InRecovery);
LWLockRelease(CLogControlLock);
}
| void ShutdownCLOG | ( | void | ) |
Definition at line 578 of file clog.c.
References ClogCtl, and SimpleLruFlush().
Referenced by ShutdownXLOG().
{
/* Flush dirty CLOG pages to disk */
TRACE_POSTGRESQL_CLOG_CHECKPOINT_START(false);
SimpleLruFlush(ClogCtl, false);
TRACE_POSTGRESQL_CLOG_CHECKPOINT_DONE(false);
}
| void StartupCLOG | ( | void | ) |
Definition at line 510 of file clog.c.
References CLogControlLock, ClogCtl, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), VariableCacheData::nextXid, ShmemVariableCache, and TransactionIdToPage.
Referenced by StartupXLOG().
{
TransactionId xid = ShmemVariableCache->nextXid;
int pageno = TransactionIdToPage(xid);
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
/*
* Initialize our idea of the latest page number.
*/
ClogCtl->shared->latest_page_number = pageno;
LWLockRelease(CLogControlLock);
}
| XidStatus TransactionIdGetStatus | ( | TransactionId | xid, | |
| XLogRecPtr * | lsn | |||
| ) |
Definition at line 389 of file clog.c.
References CLOG_XACT_BITMASK, CLogControlLock, ClogCtl, GetLSNIndex, LWLockRelease(), SimpleLruReadPage_ReadOnly(), TransactionIdToBIndex, TransactionIdToByte, and TransactionIdToPage.
Referenced by TransactionIdGetCommitLSN(), and TransactionLogFetch().
{
int pageno = TransactionIdToPage(xid);
int byteno = TransactionIdToByte(xid);
int bshift = TransactionIdToBIndex(xid) * CLOG_BITS_PER_XACT;
int slotno;
int lsnindex;
char *byteptr;
XidStatus status;
/* lock is acquired by SimpleLruReadPage_ReadOnly */
slotno = SimpleLruReadPage_ReadOnly(ClogCtl, pageno, xid);
byteptr = ClogCtl->shared->page_buffer[slotno] + byteno;
status = (*byteptr >> bshift) & CLOG_XACT_BITMASK;
lsnindex = GetLSNIndex(slotno, xid);
*lsn = ClogCtl->shared->group_lsn[lsnindex];
LWLockRelease(CLogControlLock);
return status;
}
| void TransactionIdSetTreeStatus | ( | TransactionId | xid, | |
| int | nsubxids, | |||
| TransactionId * | subxids, | |||
| XidStatus | status, | |||
| XLogRecPtr | lsn | |||
| ) |
Definition at line 145 of file clog.c.
References Assert, i, set_status_by_pages(), TRANSACTION_STATUS_ABORTED, TRANSACTION_STATUS_COMMITTED, TRANSACTION_STATUS_SUB_COMMITTED, TransactionIdSetPageStatus(), and TransactionIdToPage.
Referenced by TransactionIdAbortTree(), TransactionIdAsyncCommitTree(), and TransactionIdCommitTree().
{
int pageno = TransactionIdToPage(xid); /* get page of parent */
int i;
Assert(status == TRANSACTION_STATUS_COMMITTED ||
status == TRANSACTION_STATUS_ABORTED);
/*
* See how many subxids, if any, are on the same page as the parent, if
* any.
*/
for (i = 0; i < nsubxids; i++)
{
if (TransactionIdToPage(subxids[i]) != pageno)
break;
}
/*
* Do all items fit on a single page?
*/
if (i == nsubxids)
{
/*
* Set the parent and all subtransactions in a single call
*/
TransactionIdSetPageStatus(xid, nsubxids, subxids, status, lsn,
pageno);
}
else
{
int nsubxids_on_first_page = i;
/*
* If this is a commit then we care about doing this correctly (i.e.
* using the subcommitted intermediate status). By here, we know
* we're updating more than one page of clog, so we must mark entries
* that are *not* on the first page so that they show as subcommitted
* before we then return to update the status to fully committed.
*
* To avoid touching the first page twice, skip marking subcommitted
* for the subxids on that first page.
*/
if (status == TRANSACTION_STATUS_COMMITTED)
set_status_by_pages(nsubxids - nsubxids_on_first_page,
subxids + nsubxids_on_first_page,
TRANSACTION_STATUS_SUB_COMMITTED, lsn);
/*
* Now set the parent and subtransactions on same page as the parent,
* if any
*/
pageno = TransactionIdToPage(xid);
TransactionIdSetPageStatus(xid, nsubxids_on_first_page, subxids, status,
lsn, pageno);
/*
* Now work through the rest of the subxids one clog page at a time,
* starting from the second page onwards, like we did above.
*/
set_status_by_pages(nsubxids - nsubxids_on_first_page,
subxids + nsubxids_on_first_page,
status, lsn);
}
}
| void TrimCLOG | ( | void | ) |
Definition at line 529 of file clog.c.
References CLogControlLock, ClogCtl, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), MemSet, VariableCacheData::nextXid, ShmemVariableCache, SimpleLruReadPage(), TransactionIdToBIndex, TransactionIdToByte, TransactionIdToPage, and TransactionIdToPgIndex.
Referenced by StartupXLOG().
{
TransactionId xid = ShmemVariableCache->nextXid;
int pageno = TransactionIdToPage(xid);
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
/*
* Re-Initialize our idea of the latest page number.
*/
ClogCtl->shared->latest_page_number = pageno;
/*
* Zero out the remainder of the current clog page. Under normal
* circumstances it should be zeroes already, but it seems at least
* theoretically possible that XLOG replay will have settled on a nextXID
* value that is less than the last XID actually used and marked by the
* previous database lifecycle (since subtransaction commit writes clog
* but makes no WAL entry). Let's just be safe. (We need not worry about
* pages beyond the current one, since those will be zeroed when first
* used. For the same reason, there is no need to do anything when
* nextXid is exactly at a page boundary; and it's likely that the
* "current" page doesn't exist yet in that case.)
*/
if (TransactionIdToPgIndex(xid) != 0)
{
int byteno = TransactionIdToByte(xid);
int bshift = TransactionIdToBIndex(xid) * CLOG_BITS_PER_XACT;
int slotno;
char *byteptr;
slotno = SimpleLruReadPage(ClogCtl, pageno, false, xid);
byteptr = ClogCtl->shared->page_buffer[slotno] + byteno;
/* Zero so-far-unused positions in the current byte */
*byteptr &= (1 << bshift) - 1;
/* Zero the rest of the page */
MemSet(byteptr + 1, 0, BLCKSZ - byteno - 1);
ClogCtl->shared->page_dirty[slotno] = true;
}
LWLockRelease(CLogControlLock);
}
| void TruncateCLOG | ( | TransactionId | oldestXact | ) |
Definition at line 647 of file clog.c.
References ClogCtl, SimpleLruTruncate(), SlruScanDirCbReportPresence(), SlruScanDirectory(), TransactionIdToPage, and WriteTruncateXlogRec().
Referenced by vac_truncate_clog().
{
int cutoffPage;
/*
* The cutoff point is the start of the segment containing oldestXact. We
* pass the *page* containing oldestXact to SimpleLruTruncate.
*/
cutoffPage = TransactionIdToPage(oldestXact);
/* Check to see if there's any files that could be removed */
if (!SlruScanDirectory(ClogCtl, SlruScanDirCbReportPresence, &cutoffPage))
return; /* nothing to remove */
/* Write XLOG record and flush XLOG to disk */
WriteTruncateXlogRec(cutoffPage);
/* Now we can remove the old CLOG segment(s) */
SimpleLruTruncate(ClogCtl, cutoffPage);
}
1.7.1