mirror of
https://git.postgresql.org/git/postgresql.git
synced 2025-01-24 18:55:04 +08:00
Reorganize clog's error reporting so that PANIC on clog I/O error can
be reduced to a plain ERROR. Should make it at least a little less painful to deal with data-corruption problems.
This commit is contained in:
Tom Lane
parent
6bfa2df64e
commit
0851e12244
@ -13,7 +13,7 @@
|
||||
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Header: /cvsroot/pgsql/src/backend/access/transam/clog.c,v 1.11 2002/09/26 22:58:33 tgl Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/access/transam/clog.c,v 1.12 2003/04/14 17:31:33 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -123,7 +123,7 @@ typedef enum
|
||||
CLOG_PAGE_READ_IN_PROGRESS, /* CLOG page is being read in */
|
||||
CLOG_PAGE_CLEAN, /* CLOG page is valid and not dirty */
|
||||
CLOG_PAGE_DIRTY, /* CLOG page is valid but needs write */
|
||||
CLOG_PAGE_WRITE_IN_PROGRESS /* CLOG page is being written out in */
|
||||
CLOG_PAGE_WRITE_IN_PROGRESS /* CLOG page is being written out */
|
||||
} ClogPageStatus;
|
||||
|
||||
/*
|
||||
@ -180,12 +180,25 @@ static char ClogDir[MAXPGPATH];
|
||||
ClogCtl->page_lru_count[slotno] = 0; \
|
||||
} while (0)
|
||||
|
||||
/* Saved info for CLOGReportIOError */
|
||||
typedef enum
|
||||
{
|
||||
CLOG_OPEN_FAILED,
|
||||
CLOG_CREATE_FAILED,
|
||||
CLOG_SEEK_FAILED,
|
||||
CLOG_READ_FAILED,
|
||||
CLOG_WRITE_FAILED
|
||||
} ClogErrorCause;
|
||||
static ClogErrorCause clog_errcause;
|
||||
static int clog_errno;
|
||||
|
||||
|
||||
static int ZeroCLOGPage(int pageno, bool writeXlog);
|
||||
static int ReadCLOGPage(int pageno);
|
||||
static int ReadCLOGPage(int pageno, TransactionId xid);
|
||||
static void WriteCLOGPage(int slotno);
|
||||
static void CLOGPhysicalReadPage(int pageno, int slotno);
|
||||
static void CLOGPhysicalWritePage(int pageno, int slotno);
|
||||
static bool CLOGPhysicalReadPage(int pageno, int slotno);
|
||||
static bool CLOGPhysicalWritePage(int pageno, int slotno);
|
||||
static void CLOGReportIOError(int pageno, TransactionId xid);
|
||||
static int SelectLRUCLOGPage(int pageno);
|
||||
static bool ScanCLOGDirectory(int cutoffPage, bool doDeletions);
|
||||
static bool CLOGPagePrecedes(int page1, int page2);
|
||||
@ -212,7 +225,7 @@ TransactionIdSetStatus(TransactionId xid, XidStatus status)
|
||||
|
||||
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
|
||||
|
||||
slotno = ReadCLOGPage(pageno);
|
||||
slotno = ReadCLOGPage(pageno, xid);
|
||||
byteptr = ClogCtl->page_buffer[slotno] + byteno;
|
||||
|
||||
/* Current state should be 0 or target state */
|
||||
@ -244,7 +257,7 @@ TransactionIdGetStatus(TransactionId xid)
|
||||
|
||||
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
|
||||
|
||||
slotno = ReadCLOGPage(pageno);
|
||||
slotno = ReadCLOGPage(pageno, xid);
|
||||
byteptr = ClogCtl->page_buffer[slotno] + byteno;
|
||||
|
||||
status = (*byteptr >> bshift) & CLOG_XACT_BITMASK;
|
||||
@ -362,18 +375,22 @@ ZeroCLOGPage(int pageno, bool writeXlog)
|
||||
* Find a CLOG page in a shared buffer, reading it in if necessary.
|
||||
* The page number must correspond to an already-initialized page.
|
||||
*
|
||||
* The passed-in xid is used only for error reporting, and may be
|
||||
* InvalidTransactionId if no specific xid is associated with the action.
|
||||
*
|
||||
* Return value is the shared-buffer slot number now holding the page.
|
||||
* The buffer's LRU access info is updated.
|
||||
*
|
||||
* Control lock must be held at entry, and will be held at exit.
|
||||
*/
|
||||
static int
|
||||
ReadCLOGPage(int pageno)
|
||||
ReadCLOGPage(int pageno, TransactionId xid)
|
||||
{
|
||||
/* Outer loop handles restart if we lose the buffer to someone else */
|
||||
for (;;)
|
||||
{
|
||||
int slotno;
|
||||
bool ok;
|
||||
|
||||
/* See if page already is in memory; if not, pick victim slot */
|
||||
slotno = SelectLRUCLOGPage(pageno);
|
||||
@ -424,7 +441,7 @@ ReadCLOGPage(int pageno)
|
||||
}
|
||||
|
||||
/* Okay, do the read */
|
||||
CLOGPhysicalReadPage(pageno, slotno);
|
||||
ok = CLOGPhysicalReadPage(pageno, slotno);
|
||||
|
||||
/* Re-acquire shared control lock and update page state */
|
||||
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
|
||||
@ -432,10 +449,14 @@ ReadCLOGPage(int pageno)
|
||||
Assert(ClogCtl->page_number[slotno] == pageno &&
|
||||
ClogCtl->page_status[slotno] == CLOG_PAGE_READ_IN_PROGRESS);
|
||||
|
||||
ClogCtl->page_status[slotno] = CLOG_PAGE_CLEAN;
|
||||
ClogCtl->page_status[slotno] = ok ? CLOG_PAGE_CLEAN : CLOG_PAGE_EMPTY;
|
||||
|
||||
LWLockRelease(ClogBufferLocks[slotno]);
|
||||
|
||||
/* Now it's okay to elog if we failed */
|
||||
if (!ok)
|
||||
CLOGReportIOError(pageno, xid);
|
||||
|
||||
ClogRecentlyUsed(slotno);
|
||||
return slotno;
|
||||
}
|
||||
@ -456,6 +477,7 @@ static void
|
||||
WriteCLOGPage(int slotno)
|
||||
{
|
||||
int pageno;
|
||||
bool ok;
|
||||
|
||||
/* Do nothing if page does not need writing */
|
||||
if (ClogCtl->page_status[slotno] != CLOG_PAGE_DIRTY &&
|
||||
@ -499,7 +521,7 @@ WriteCLOGPage(int slotno)
|
||||
ClogCtl->page_status[slotno] = CLOG_PAGE_WRITE_IN_PROGRESS;
|
||||
|
||||
/* Okay, do the write */
|
||||
CLOGPhysicalWritePage(pageno, slotno);
|
||||
ok = CLOGPhysicalWritePage(pageno, slotno);
|
||||
|
||||
/* Re-acquire shared control lock and update page state */
|
||||
LWLockAcquire(CLogControlLock, LW_EXCLUSIVE);
|
||||
@ -510,18 +532,26 @@ WriteCLOGPage(int slotno)
|
||||
|
||||
/* Cannot set CLEAN if someone re-dirtied page since write started */
|
||||
if (ClogCtl->page_status[slotno] == CLOG_PAGE_WRITE_IN_PROGRESS)
|
||||
ClogCtl->page_status[slotno] = CLOG_PAGE_CLEAN;
|
||||
ClogCtl->page_status[slotno] = ok ? CLOG_PAGE_CLEAN : CLOG_PAGE_DIRTY;
|
||||
|
||||
LWLockRelease(ClogBufferLocks[slotno]);
|
||||
|
||||
/* Now it's okay to elog if we failed */
|
||||
if (!ok)
|
||||
CLOGReportIOError(pageno, InvalidTransactionId);
|
||||
}
|
||||
|
||||
/*
|
||||
* Physical read of a (previously existing) page into a buffer slot
|
||||
*
|
||||
* On failure, we cannot just elog(ERROR) since caller has put state in
|
||||
* shared memory that must be undone. So, we return FALSE and save enough
|
||||
* info in static variables to let CLOGReportIOError make the report.
|
||||
*
|
||||
* For now, assume it's not worth keeping a file pointer open across
|
||||
* read/write operations. We could cache one virtual file pointer ...
|
||||
*/
|
||||
static void
|
||||
static bool
|
||||
CLOGPhysicalReadPage(int pageno, int slotno)
|
||||
{
|
||||
int segno = pageno / CLOG_PAGES_PER_SEGMENT;
|
||||
@ -543,31 +573,47 @@ CLOGPhysicalReadPage(int pageno, int slotno)
|
||||
if (fd < 0)
|
||||
{
|
||||
if (errno != ENOENT || !InRecovery)
|
||||
elog(PANIC, "open of %s failed: %m", path);
|
||||
{
|
||||
clog_errcause = CLOG_OPEN_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
elog(LOG, "clog file %s doesn't exist, reading as zeroes", path);
|
||||
MemSet(ClogCtl->page_buffer[slotno], 0, CLOG_BLCKSZ);
|
||||
return;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (lseek(fd, (off_t) offset, SEEK_SET) < 0)
|
||||
elog(PANIC, "lseek of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
{
|
||||
clog_errcause = CLOG_SEEK_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
errno = 0;
|
||||
if (read(fd, ClogCtl->page_buffer[slotno], CLOG_BLCKSZ) != CLOG_BLCKSZ)
|
||||
elog(PANIC, "read of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
{
|
||||
clog_errcause = CLOG_READ_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
close(fd);
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* Physical write of a page from a buffer slot
|
||||
*
|
||||
* On failure, we cannot just elog(ERROR) since caller has put state in
|
||||
* shared memory that must be undone. So, we return FALSE and save enough
|
||||
* info in static variables to let CLOGReportIOError make the report.
|
||||
*
|
||||
* For now, assume it's not worth keeping a file pointer open across
|
||||
* read/write operations. We could cache one virtual file pointer ...
|
||||
*/
|
||||
static void
|
||||
static bool
|
||||
CLOGPhysicalWritePage(int pageno, int slotno)
|
||||
{
|
||||
int segno = pageno / CLOG_PAGES_PER_SEGMENT;
|
||||
@ -595,16 +641,28 @@ CLOGPhysicalWritePage(int pageno, int slotno)
|
||||
if (fd < 0)
|
||||
{
|
||||
if (errno != ENOENT)
|
||||
elog(PANIC, "open of %s failed: %m", path);
|
||||
{
|
||||
clog_errcause = CLOG_OPEN_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
fd = BasicOpenFile(path, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
|
||||
S_IRUSR | S_IWUSR);
|
||||
if (fd < 0)
|
||||
elog(PANIC, "creation of file %s failed: %m", path);
|
||||
{
|
||||
clog_errcause = CLOG_CREATE_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
if (lseek(fd, (off_t) offset, SEEK_SET) < 0)
|
||||
elog(PANIC, "lseek of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
{
|
||||
clog_errcause = CLOG_SEEK_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
errno = 0;
|
||||
if (write(fd, ClogCtl->page_buffer[slotno], CLOG_BLCKSZ) != CLOG_BLCKSZ)
|
||||
@ -612,11 +670,56 @@ CLOGPhysicalWritePage(int pageno, int slotno)
|
||||
/* if write didn't set errno, assume problem is no disk space */
|
||||
if (errno == 0)
|
||||
errno = ENOSPC;
|
||||
elog(PANIC, "write of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
clog_errcause = CLOG_WRITE_FAILED;
|
||||
clog_errno = errno;
|
||||
return false;
|
||||
}
|
||||
|
||||
close(fd);
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* Issue the error message after failure of CLOGPhysicalReadPage or
|
||||
* CLOGPhysicalWritePage. Call this after cleaning up shared-memory state.
|
||||
*/
|
||||
static void
|
||||
CLOGReportIOError(int pageno, TransactionId xid)
|
||||
{
|
||||
int segno = pageno / CLOG_PAGES_PER_SEGMENT;
|
||||
int rpageno = pageno % CLOG_PAGES_PER_SEGMENT;
|
||||
int offset = rpageno * CLOG_BLCKSZ;
|
||||
char path[MAXPGPATH];
|
||||
|
||||
/* XXX TODO: provide xid as context in error messages */
|
||||
|
||||
ClogFileName(path, segno);
|
||||
errno = clog_errno;
|
||||
switch (clog_errcause)
|
||||
{
|
||||
case CLOG_OPEN_FAILED:
|
||||
elog(ERROR, "open of %s failed: %m", path);
|
||||
break;
|
||||
case CLOG_CREATE_FAILED:
|
||||
elog(ERROR, "creation of file %s failed: %m", path);
|
||||
break;
|
||||
case CLOG_SEEK_FAILED:
|
||||
elog(ERROR, "lseek of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
break;
|
||||
case CLOG_READ_FAILED:
|
||||
elog(ERROR, "read of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
break;
|
||||
case CLOG_WRITE_FAILED:
|
||||
elog(ERROR, "write of clog file %u, offset %u failed: %m",
|
||||
segno, offset);
|
||||
break;
|
||||
default:
|
||||
/* can't get here, we trust */
|
||||
elog(ERROR, "unknown CLOG I/O error");
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
@ -679,7 +782,8 @@ SelectLRUCLOGPage(int pageno)
|
||||
* the read to complete.
|
||||
*/
|
||||
if (ClogCtl->page_status[bestslot] == CLOG_PAGE_READ_IN_PROGRESS)
|
||||
(void) ReadCLOGPage(ClogCtl->page_number[bestslot]);
|
||||
(void) ReadCLOGPage(ClogCtl->page_number[bestslot],
|
||||
InvalidTransactionId);
|
||||
else
|
||||
WriteCLOGPage(bestslot);
|
||||
|
||||
@ -857,7 +961,8 @@ restart:;
|
||||
* This is the same logic as in SelectLRUCLOGPage.
|
||||
*/
|
||||
if (ClogCtl->page_status[slotno] == CLOG_PAGE_READ_IN_PROGRESS)
|
||||
(void) ReadCLOGPage(ClogCtl->page_number[slotno]);
|
||||
(void) ReadCLOGPage(ClogCtl->page_number[slotno],
|
||||
InvalidTransactionId);
|
||||
else
|
||||
WriteCLOGPage(slotno);
|
||||
goto restart;
|
||||
@ -886,7 +991,7 @@ ScanCLOGDirectory(int cutoffPage, bool doDeletions)
|
||||
|
||||
cldir = opendir(ClogDir);
|
||||
if (cldir == NULL)
|
||||
elog(PANIC, "could not open transaction-commit log directory (%s): %m",
|
||||
elog(ERROR, "could not open transaction-commit log directory (%s): %m",
|
||||
ClogDir);
|
||||
|
||||
errno = 0;
|
||||
@ -911,7 +1016,7 @@ ScanCLOGDirectory(int cutoffPage, bool doDeletions)
|
||||
errno = 0;
|
||||
}
|
||||
if (errno)
|
||||
elog(PANIC, "could not read transaction-commit log directory (%s): %m",
|
||||
elog(ERROR, "could not read transaction-commit log directory (%s): %m",
|
||||
ClogDir);
|
||||
closedir(cldir);
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user