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This commit is contained in:
Vadim B. Mikheev
1997-11-02 15:27:14 +00:00
parent 6cc0a00dec
commit 32cd09ac6d
36 changed files with 265 additions and 1841 deletions
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127
src/backend/access/transam/transam.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/transam/transam.c,v 1.13 1997/09/08 21:41:42 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/access/transam/transam.c,v 1.14 1997/11/02 15:24:42 vadim Exp $
*
* NOTES
* This file contains the high level access-method interface to the
@ -41,17 +41,14 @@ TransactionLogUpdate(TransactionId transactionId,
*/
Relation LogRelation = (Relation) NULL;
Relation TimeRelation = (Relation) NULL;
Relation VariableRelation = (Relation) NULL;
/* ----------------
* global variables holding cached transaction id's and statuses.
* ----------------
*/
TransactionId cachedGetCommitTimeXid;
AbsoluteTime cachedGetCommitTime;
TransactionId cachedTestXid;
XidStatus cachedTestXidStatus;
TransactionId cachedTestXid;
XidStatus cachedTestXidStatus;
/* ----------------
* transaction system constants
@ -118,7 +115,7 @@ SetRecoveryCheckingEnabled(bool state)
#endif
/* ----------------------------------------------------------------
* postgres log/time access method interface
* postgres log access method interface
*
* TransactionLogTest
* TransactionLogUpdate
@ -204,7 +201,6 @@ TransactionLogUpdate(TransactionId transactionId, /* trans id to update */
{
BlockNumber blockNumber;
bool fail = false; /* success/failure */
AbsoluteTime currentTime; /* time of this transaction */
/* ----------------
* during initialization we don't record any updates.
@ -213,12 +209,6 @@ TransactionLogUpdate(TransactionId transactionId, /* trans id to update */
if (!RelationIsValid(LogRelation))
return;
/* ----------------
* get the transaction commit time
* ----------------
*/
currentTime = getSystemTime();
/* ----------------
* update the log relation
* ----------------
@ -234,91 +224,12 @@ TransactionLogUpdate(TransactionId transactionId, /* trans id to update */
* update (invalidate) our single item TransactionLogTest cache.
* ----------------
*/
TransactionIdStore(transactionId, &cachedTestXid);
cachedTestXidStatus = status;
/* ----------------
* now we update the time relation, if necessary
* (we only record commit times)
* ----------------
*/
if (RelationIsValid(TimeRelation) && status == XID_COMMIT)
if (status != XID_COMMIT)
{
TransComputeBlockNumber(TimeRelation, transactionId, &blockNumber);
TransBlockNumberSetCommitTime(TimeRelation,
blockNumber,
transactionId,
currentTime,
&fail);
/* ----------------
* update (invalidate) our single item GetCommitTime cache.
* ----------------
*/
TransactionIdStore(transactionId, &cachedGetCommitTimeXid);
cachedGetCommitTime = currentTime;
TransactionIdStore(transactionId, &cachedTestXid);
cachedTestXidStatus = status;
}
/* ----------------
* now we update the "last committed transaction" field
* in the variable relation if we are recording a commit.
* ----------------
*/
if (RelationIsValid(VariableRelation) && status == XID_COMMIT)
UpdateLastCommittedXid(transactionId);
}
/* --------------------------------
* TransactionIdGetCommitTime
* --------------------------------
*/
AbsoluteTime /* commit time of transaction id */
TransactionIdGetCommitTime(TransactionId transactionId) /* transaction id to
* test */
{
BlockNumber blockNumber;
AbsoluteTime commitTime; /* commit time */
bool fail = false; /* success/failure */
/* ----------------
* return invalid if we aren't running yet...
* ----------------
*/
if (!RelationIsValid(TimeRelation))
return INVALID_ABSTIME;
/* ----------------
* before going to the buffer manager, check our single
* item cache to see if we didn't just get the commit time
* a moment ago.
* ----------------
*/
if (TransactionIdEquals(transactionId, cachedGetCommitTimeXid))
return cachedGetCommitTime;
/* ----------------
* compute the item pointer corresponding to the
* page containing our transaction commit time
* ----------------
*/
TransComputeBlockNumber(TimeRelation, transactionId, &blockNumber);
commitTime = TransBlockNumberGetCommitTime(TimeRelation,
blockNumber,
transactionId,
&fail);
/* ----------------
* update our cache and return the transaction commit time
* ----------------
*/
if (!fail)
{
TransactionIdStore(transactionId, &cachedGetCommitTimeXid);
cachedGetCommitTime = commitTime;
return commitTime;
}
else
return INVALID_ABSTIME;
}
/* ----------------------------------------------------------------
@ -472,7 +383,6 @@ void
InitializeTransactionLog(void)
{
Relation logRelation;
Relation timeRelation;
MemoryContext oldContext;
/* ----------------
@ -503,20 +413,17 @@ InitializeTransactionLog(void)
* ----------------
*/
logRelation = heap_openr(LogRelationName);
timeRelation = heap_openr(TimeRelationName);
VariableRelation = heap_openr(VariableRelationName);
/* ----------------
* XXX TransactionLogUpdate requires that LogRelation
* and TimeRelation are valid so we temporarily set
* them so we can initialize things properly.
* This could be done cleaner.
* is valid so we temporarily set it so we can initialize
* things properly. This could be done cleaner.
* ----------------
*/
LogRelation = logRelation;
TimeRelation = timeRelation;
/* ----------------
* if we have a virgin database, we initialize the log and time
* if we have a virgin database, we initialize the log
* relation by committing the AmiTransactionId (id 512) and we
* initialize the variable relation by setting the next available
* transaction id to FirstTransactionId (id 514). OID initialization
@ -529,10 +436,12 @@ InitializeTransactionLog(void)
/* ----------------
* SOMEDAY initialize the information stored in
* the headers of the log/time/variable relations.
* the headers of the log/variable relations.
* ----------------
*/
TransactionLogUpdate(AmiTransactionId, XID_COMMIT);
TransactionIdStore(AmiTransactionId, &cachedTestXid);
cachedTestXidStatus = XID_COMMIT;
VariableRelationPutNextXid(FirstTransactionId);
}
@ -547,7 +456,6 @@ InitializeTransactionLog(void)
TransRecover(logRelation);
}
LogRelation = (Relation) NULL;
TimeRelation = (Relation) NULL;
SpinRelease(OidGenLockId);
/* ----------------
@ -561,7 +469,6 @@ InitializeTransactionLog(void)
* ----------------
*/
LogRelation = logRelation;
TimeRelation = timeRelation;
/* ----------------
* restore the memory context to the previous context
@ -651,15 +558,7 @@ TransactionIdCommit(TransactionId transactionId)
if (AMI_OVERRIDE)
return;
/*
* Within TransactionLogUpdate we call UpdateLastCommited() which
* assumes we have exclusive access to pg_variable. Therefore we need
* to get exclusive access before calling TransactionLogUpdate. -mer
* 18 Aug 1992
*/
SpinAcquire(OidGenLockId);
TransactionLogUpdate(transactionId, XID_COMMIT);
SpinRelease(OidGenLockId);
}
/*