@ -7,7 +7,7 @@
* Portions Copyright ( c ) 1996 - 2006 , PostgreSQL Global Development Group
* Portions Copyright ( c ) 1994 , Regents of the University of California
*
* $ PostgreSQL : pgsql / src / backend / access / transam / xlog . c , v 1.247 2006 / 08 / 07 16 : 57 : 56 tgl Exp $
* $ PostgreSQL : pgsql / src / backend / access / transam / xlog . c , v 1.248 2006 / 08 / 17 23 : 04 : 05 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -23,6 +23,7 @@
# include <sys/time.h>
# include "access/clog.h"
# include "access/heapam.h"
# include "access/multixact.h"
# include "access/subtrans.h"
# include "access/transam.h"
@ -32,6 +33,8 @@
# include "access/xlogutils.h"
# include "catalog/catversion.h"
# include "catalog/pg_control.h"
# include "catalog/pg_type.h"
# include "funcapi.h"
# include "miscadmin.h"
# include "pgstat.h"
# include "postmaster/bgwriter.h"
@ -128,6 +131,7 @@
/* User-settable parameters */
int CheckPointSegments = 3 ;
int XLOGbuffers = 8 ;
int XLogArchiveTimeout = 0 ;
char * XLogArchiveCommand = NULL ;
char * XLOG_sync_method = NULL ;
const char XLOG_sync_method_default [ ] = DEFAULT_SYNC_METHOD_STR ;
@ -347,8 +351,9 @@ typedef struct XLogCtlInsert
*/
typedef struct XLogCtlWrite
{
XLogwrtResult LogwrtResult ; /* current value of LogwrtResult */
int curridx ; /* cache index of next block to write */
XLogwrtResult LogwrtResult ; /* current value of LogwrtResult */
int curridx ; /* cache index of next block to write */
time_t lastSegSwitchTime ; /* time of last xlog segment switch */
} XLogCtlWrite ;
/*
@ -1660,7 +1665,8 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible, bool xlog_switch)
* switch .
*
* This is also the right place to notify the Archiver that the
* segment is ready to copy to archival storage .
* segment is ready to copy to archival storage , and to update
* the timer for archive_timeout .
*/
if ( finishing_seg | | ( xlog_switch & & last_iteration ) )
{
@ -1669,6 +1675,8 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible, bool xlog_switch)
if ( XLogArchivingActive ( ) )
XLogArchiveNotifySeg ( openLogId , openLogSeg ) ;
Write - > lastSegSwitchTime = time ( NULL ) ;
}
}
@ -5124,6 +5132,9 @@ StartupXLOG(void)
ControlFile - > time = time ( NULL ) ;
UpdateControlFile ( ) ;
/* start the archive_timeout timer running */
XLogCtl - > Write . lastSegSwitchTime = ControlFile - > time ;
/* Start up the commit log and related stuff, too */
StartupCLOG ( ) ;
StartupSUBTRANS ( oldestActiveXID ) ;
@ -5307,6 +5318,22 @@ GetRedoRecPtr(void)
return RedoRecPtr ;
}
/*
* Get the time of the last xlog segment switch
*/
time_t
GetLastSegSwitchTime ( void )
{
time_t result ;
/* Need WALWriteLock, but shared lock is sufficient */
LWLockAcquire ( WALWriteLock , LW_SHARED ) ;
result = XLogCtl - > Write . lastSegSwitchTime ;
LWLockRelease ( WALWriteLock ) ;
return result ;
}
/*
* GetRecentNextXid - get the nextXid value saved by the most recent checkpoint
*
@ -5728,7 +5755,7 @@ XLogPutNextOid(Oid nextOid)
* or the end + 1 address of the prior segment if we did not need to
* write a switch record because we are already at segment start .
*/
static XLogRecPtr
XLogRecPtr
RequestXLogSwitch ( void )
{
XLogRecPtr RecPtr ;
@ -6335,10 +6362,43 @@ pg_switch_xlog(PG_FUNCTION_ARGS)
}
/*
* Report the current WAL location ( same format as pg_start_backup etc )
* Report the current WAL write location ( same format as pg_start_backup etc )
*
* This is useful for determining how much of WAL is visible to an external
* archiving process . Note that the data before this point is written out
* to the kernel , but is not necessarily synced to disk .
*/
Datum
pg_current_xlog_location ( PG_FUNCTION_ARGS )
{
text * result ;
char location [ MAXFNAMELEN ] ;
/* Make sure we have an up-to-date local LogwrtResult */
{
/* use volatile pointer to prevent code rearrangement */
volatile XLogCtlData * xlogctl = XLogCtl ;
SpinLockAcquire ( & xlogctl - > info_lck ) ;
LogwrtResult = xlogctl - > LogwrtResult ;
SpinLockRelease ( & xlogctl - > info_lck ) ;
}
snprintf ( location , sizeof ( location ) , " %X/%X " ,
LogwrtResult . Write . xlogid , LogwrtResult . Write . xrecoff ) ;
result = DatumGetTextP ( DirectFunctionCall1 ( textin ,
CStringGetDatum ( location ) ) ) ;
PG_RETURN_TEXT_P ( result ) ;
}
/*
* Report the current WAL insert location ( same format as pg_start_backup etc )
*
* This function is mostly for debugging purposes .
*/
Datum
pg_current_xlog_insert_location ( PG_FUNCTION_ARGS )
{
text * result ;
XLogCtlInsert * Insert = & XLogCtl - > Insert ;
@ -6372,7 +6432,6 @@ Datum
pg_xlogfile_name_offset ( PG_FUNCTION_ARGS )
{
text * location = PG_GETARG_TEXT_P ( 0 ) ;
text * result ;
char * locationstr ;
unsigned int uxlogid ;
unsigned int uxrecoff ;
@ -6381,7 +6440,15 @@ pg_xlogfile_name_offset(PG_FUNCTION_ARGS)
uint32 xrecoff ;
XLogRecPtr locationpoint ;
char xlogfilename [ MAXFNAMELEN ] ;
Datum values [ 2 ] ;
bool isnull [ 2 ] ;
TupleDesc resultTupleDesc ;
HeapTuple resultHeapTuple ;
Datum result ;
/*
* Read input and parse
*/
locationstr = DatumGetCString ( DirectFunctionCall1 ( textout ,
PointerGetDatum ( location ) ) ) ;
@ -6394,18 +6461,44 @@ pg_xlogfile_name_offset(PG_FUNCTION_ARGS)
locationpoint . xlogid = uxlogid ;
locationpoint . xrecoff = uxrecoff ;
/*
* Construct a tuple descriptor for the result row . This must match
* this function ' s pg_proc entry !
*/
resultTupleDesc = CreateTemplateTupleDesc ( 2 , false ) ;
TupleDescInitEntry ( resultTupleDesc , ( AttrNumber ) 1 , " file_name " ,
TEXTOID , - 1 , 0 ) ;
TupleDescInitEntry ( resultTupleDesc , ( AttrNumber ) 2 , " file_offset " ,
INT4OID , - 1 , 0 ) ;
resultTupleDesc = BlessTupleDesc ( resultTupleDesc ) ;
/*
* xlogfilename
*/
XLByteToPrevSeg ( locationpoint , xlogid , xlogseg ) ;
XLogFileName ( xlogfilename , ThisTimeLineID , xlogid , xlogseg ) ;
values [ 0 ] = DirectFunctionCall1 ( textin ,
CStringGetDatum ( xlogfilename ) ) ;
isnull [ 0 ] = false ;
/*
* offset
*/
xrecoff = locationpoint . xrecoff - xlogseg * XLogSegSize ;
snprintf ( xlogfilename + strlen ( xlogfilename ) ,
sizeof ( xlogfilename ) - strlen ( xlogfilename ) ,
" %u " ,
( unsigned int ) xrecoff ) ;
result = DatumGetTextP ( DirectFunctionCall1 ( textin ,
CStringGetDatum ( xlogfilename ) ) ) ;
PG_RETURN_TEXT_P ( result ) ;
values [ 1 ] = UInt32GetDatum ( xrecoff ) ;
isnull [ 1 ] = false ;
/*
* Tuple jam : Having first prepared your Datums , then squash together
*/
resultHeapTuple = heap_form_tuple ( resultTupleDesc , values , isnull ) ;
result = HeapTupleGetDatum ( resultHeapTuple ) ;
PG_RETURN_DATUM ( result ) ;
}
/*
Tom Lane
20 years ago