Re: [HACKERS] Subtransaction commits and Hot Standby
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Re: [HACKERS] Subtransaction commits and Hot Standby
by Simon Riggs
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On Tue, 2008-09-23 at 22:47 +0100, Simon Riggs wrote: > I've tested this some more and am much happier with it now. The concept is fine, but I've found a coding bug in further testing. Please wait now for new version before review. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-patches mailing list (pgsql-patches@...) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches |
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Re: [HACKERS] Subtransaction commits and Hot Standby
by Simon Riggs
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On Wed, 2008-09-24 at 13:48 +0100, Simon Riggs wrote: > On Tue, 2008-09-23 at 22:47 +0100, Simon Riggs wrote: > > > I've tested this some more and am much happier with it now. > > The concept is fine, but I've found a coding bug in further testing. > Please wait now for new version before review. OK, spent long time testing various batching scenarios for this using a custom test harness to simulate various spreads of xids in transaction trees. All looks fine now. The main work is done in new clog.c functions: TransactionIdSetTreeStatus() which sets whole tree atomically by calling TransactionIdSetPageStatus(), which in turn calls TransactionIdSetStatusBit() for each xid status change. TransactionIdSetPageStatus() performs locking and handles write_ok problem, as did code it replaces. TransactionIdSetPageStatus() is called theoretical minimum number of times for any transaction tree. Patch slightly fumbles diff-ing new and replacement code, so there are two chunks that appear to show I'm removing locking. I'm not!! Everything else is just API changes. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support [atomic_subxids.v4.patch] Index: src/backend/access/transam/README =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/backend/access/transam/README,v retrieving revision 1.11 diff -c -r1.11 README *** src/backend/access/transam/README 21 Mar 2008 13:23:28 -0000 1.11 --- src/backend/access/transam/README 24 Sep 2008 17:33:23 -0000 *************** *** 342,351 **** an XID. A transaction can be in progress, committed, aborted, or "sub-committed". This last state means that it's a subtransaction that's no longer running, but its parent has not updated its state yet (either it is ! still running, or the backend crashed without updating its status). A ! sub-committed transaction's status will be updated again to the final value as ! soon as the parent commits or aborts, or when the parent is detected to be ! aborted. Savepoints are implemented using subtransactions. A subtransaction is a transaction inside a transaction; its commit or abort status is not only --- 342,360 ---- an XID. A transaction can be in progress, committed, aborted, or "sub-committed". This last state means that it's a subtransaction that's no longer running, but its parent has not updated its state yet (either it is ! still running, or the backend crashed without updating its status). Prior ! to 8.4 we updated the status to sub-committed in clog as soon as ! sub-commit had happened. It was later realised that this is not actually ! required for any purpose and the action can be deferred until transaction ! commit. The main role of marking transactions as sub-committed is to ! provide an atomic commit protocol when transaction status is spread across ! multiple clog pages. As a result whenever transaction status spreads ! across multiple pages we must use a two-phase commit protocol. The first ! phase is to mark the subtransactions as sub-committed, then we mark the ! top level transaction and all its subtransactions committed (in that order). ! So in 8.4 sub-committed state still exists, but as a transitory state as ! part of final commit. Subtransaction abort is always marked in clog as ! soon as it occurs, to allow locks to be released. Savepoints are implemented using subtransactions. A subtransaction is a transaction inside a transaction; its commit or abort status is not only Index: src/backend/access/transam/clog.c =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/backend/access/transam/clog.c,v retrieving revision 1.47 diff -c -r1.47 clog.c *** src/backend/access/transam/clog.c 1 Aug 2008 13:16:08 -0000 1.47 --- src/backend/access/transam/clog.c 24 Sep 2008 21:24:02 -0000 *************** *** 80,89 **** static bool CLOGPagePrecedes(int page1, int page2); static void WriteZeroPageXlogRec(int pageno); static void WriteTruncateXlogRec(int pageno); ! ! ! /* ! * Record the final state of a transaction in the commit log. * * lsn must be the WAL location of the commit record when recording an async * commit. For a synchronous commit it can be InvalidXLogRecPtr, since the --- 80,105 ---- static bool CLOGPagePrecedes(int page1, int page2); static void WriteZeroPageXlogRec(int pageno); static void WriteTruncateXlogRec(int pageno); ! static void TransactionIdSetPageStatus(TransactionId xid, int nsubxids, ! TransactionId *subxids, XidStatus status, XLogRecPtr lsn, int pageno, bool subcommit); ! static void TransactionIdSetStatusBit(TransactionId xid, XidStatus status, ! XLogRecPtr lsn, int slotno); ! ! /* ! * TransactionIdSetTreeStatus ! * ! * Record the final state of transaction entries in the commit log for ! * a transaction and its subtransaction tree. Take care to ensure this is ! * both atomic and efficient. Prior to 8.4, this capability was provided ! * by the non-atomic TransactionIdSetStatus, which is replaced by this ! * new atomic version. ! * ! * xid is a single xid to set status for. This will typically be ! * the top level transactionid for a top level commit or abort. It can ! * also be a subtransaction when we record transaction aborts. ! * ! * subxids is an array of xids of length nsubxids, representing subtransactions ! * in the tree of xid. In various cases nsubxids may be zero. * * lsn must be the WAL location of the commit record when recording an async * commit. For a synchronous commit it can be InvalidXLogRecPtr, since the *************** *** 91,107 **** * should be InvalidXLogRecPtr for abort cases, too. * * NB: this is a low-level routine and is NOT the preferred entry point ! * for most uses; TransactionLogUpdate() in transam.c is the intended caller. */ void ! TransactionIdSetStatus(TransactionId xid, XidStatus status, XLogRecPtr lsn) { - int pageno = TransactionIdToPage(xid); - int byteno = TransactionIdToByte(xid); - int bshift = TransactionIdToBIndex(xid) * CLOG_BITS_PER_XACT; int slotno; ! char *byteptr; ! char byteval; Assert(status == TRANSACTION_STATUS_COMMITTED || status == TRANSACTION_STATUS_ABORTED || --- 107,238 ---- * should be InvalidXLogRecPtr for abort cases, too. * * NB: this is a low-level routine and is NOT the preferred entry point ! * for most uses; functions in in transam.c are the intended callers. ! * ! * Note that no lock requests are made at this level, only lower functions. ! * ! * XXX Think about issuing FADVISE_WILLNEED on pages that we will need, ! * but aren't yet in cache, as well as hinting pages not to fall out of ! * cache yet. */ void ! TransactionIdSetTreeStatus(TransactionId xid, int nsubxids, ! TransactionId *subxids, XidStatus status, XLogRecPtr lsn) ! { ! 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 any subtransactions on same page as it ! */ ! TransactionIdSetPageStatus(xid, nsubxids, subxids, status, lsn, ! pageno, true); ! } ! else ! { ! int num_on_first_page = i; ! int num_on_page = 0; ! int offset; ! ! if (status == TRANSACTION_STATUS_COMMITTED) ! { ! /* ! * If this is a commit then we care about doing this atomically. ! * 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. ! * We don't mark the first page because we will be doing that ! * when we mark the main commit, so we wish to avoid touching ! * that page twice. ! */ ! num_on_page = 0; ! i = offset = num_on_first_page; ! pageno = TransactionIdToPage(subxids[num_on_first_page]); ! while (i < nsubxids) ! { ! while (TransactionIdToPage(subxids[i]) == pageno && i < nsubxids) ! { ! num_on_page++; ! i++; ! } ! ! TransactionIdSetPageStatus(InvalidTransactionId, ! num_on_page, subxids + offset, ! TRANSACTION_STATUS_SUB_COMMITTED, lsn, pageno, true); ! offset = i; ! num_on_page = 0; ! pageno = TransactionIdToPage(subxids[offset]); ! } ! } ! ! /* ! * Now set the parent and subtransactions on same page as it, if any ! */ ! pageno = TransactionIdToPage(xid); ! TransactionIdSetPageStatus(xid, num_on_first_page, subxids, status, lsn, ! pageno, true); ! ! /* ! * By now, all subtransactions have been subcommitted, so all calls ! * to TransactionIdSetPageStatus() will use subcommit=false after ! * this point for this transaction tree. ! */ ! ! /* ! * Now work through the rest of the subxids one clog page at a time, ! * starting from the second page onwards, like we did above. ! */ ! num_on_page = 0; ! i = offset = num_on_first_page; ! pageno = TransactionIdToPage(subxids[num_on_first_page]); ! while (i < nsubxids) ! { ! while (TransactionIdToPage(subxids[i]) == pageno && i < nsubxids) ! { ! num_on_page++; ! i++; ! } ! ! TransactionIdSetPageStatus(InvalidTransactionId, ! num_on_page, subxids + offset, ! status, lsn, pageno, false); ! offset = i; ! num_on_page = 0; ! pageno = TransactionIdToPage(subxids[offset]); ! } ! } ! } ! ! /* ! * Record the final state of transaction entries in the commit log for ! * all entries on *one* page only. Atomic only on this page. ! * ! * Otherwise API is same as TransactionIdSetTreeStatus() ! */ ! static void ! TransactionIdSetPageStatus(TransactionId xid, int nsubxids, ! TransactionId *subxids, XidStatus status, XLogRecPtr lsn, int pageno, bool subcommit) { int slotno; ! int i; Assert(status == TRANSACTION_STATUS_COMMITTED || status == TRANSACTION_STATUS_ABORTED || *************** *** 116,124 **** * mustn't let it reach disk until we've done the appropriate WAL flush. * But when lsn is invalid, it's OK to scribble on a page while it is * write-busy, since we don't care if the update reaches disk sooner than ! * we think. Hence, pass write_ok = XLogRecPtrIsInvalid(lsn). */ slotno = SimpleLruReadPage(ClogCtl, pageno, XLogRecPtrIsInvalid(lsn), xid); byteptr = ClogCtl->shared->page_buffer[slotno] + byteno; /* Current state should be 0, subcommitted or target state */ --- 247,303 ---- * mustn't let it reach disk until we've done the appropriate WAL flush. * But when lsn is invalid, it's OK to scribble on a page while it is * write-busy, since we don't care if the update reaches disk sooner than ! * we think. */ slotno = SimpleLruReadPage(ClogCtl, pageno, XLogRecPtrIsInvalid(lsn), xid); + + /* + * If we synch commit more than one xid on this page while write busy + * we might find that some of the bits go to disk and others don't. + * That would break atomicity, so if we haven't already subcommitted + * the xids for this commit, we do that first and then come back + * to start marking commits. If using async commit then we already + * waited for the write I/O to complete by this point, so nothing to do. + */ + if (subcommit && status == TRANSACTION_STATUS_COMMITTED && + XLogRecPtrIsInvalid(lsn)) + { + for (i = 0; i < nsubxids; i++) + { + Assert(ClogCtl->shared->page_number[slotno] == TransactionIdToPage(subxids[i])); + TransactionIdSetStatusBit(subxids[i], + TRANSACTION_STATUS_SUB_COMMITTED, lsn, slotno); + } + } + + + /* Set the main transaction id, if any */ + if (TransactionIdIsValid(xid)) + TransactionIdSetStatusBit(xid, status, lsn, slotno); + + /* Set the subtransactions on this page only */ + for (i = 0; i < nsubxids; i++) + { + Assert(ClogCtl->shared->page_number[slotno] == TransactionIdToPage(subxids[i])); + TransactionIdSetStatusBit(subxids[i], status, lsn, slotno); + } + + ClogCtl->shared->page_dirty[slotno] = true; + + LWLockRelease(CLogControlLock); + } + + /* + * Must be called with CLogControlLock held + */ + static void + TransactionIdSetStatusBit(TransactionId xid, XidStatus status, XLogRecPtr lsn, int slotno) + { + int byteno = TransactionIdToByte(xid); + int bshift = TransactionIdToBIndex(xid) * CLOG_BITS_PER_XACT; + char *byteptr; + char byteval; + byteptr = ClogCtl->shared->page_buffer[slotno] + byteno; /* Current state should be 0, subcommitted or target state */ *************** *** 132,139 **** byteval |= (status << bshift); *byteptr = byteval; - ClogCtl->shared->page_dirty[slotno] = true; - /* * Update the group LSN if the transaction completion LSN is higher. * --- 311,316 ---- *************** *** 149,156 **** if (XLByteLT(ClogCtl->shared->group_lsn[lsnindex], lsn)) ClogCtl->shared->group_lsn[lsnindex] = lsn; } - - LWLockRelease(CLogControlLock); } /* --- 326,331 ---- Index: src/backend/access/transam/transam.c =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/backend/access/transam/transam.c,v retrieving revision 1.76 diff -c -r1.76 transam.c *** src/backend/access/transam/transam.c 26 Mar 2008 18:48:59 -0000 1.76 --- src/backend/access/transam/transam.c 24 Sep 2008 17:33:23 -0000 *************** *** 40,54 **** /* Local functions */ static XidStatus TransactionLogFetch(TransactionId transactionId); - static void TransactionLogUpdate(TransactionId transactionId, - XidStatus status, XLogRecPtr lsn); /* ---------------------------------------------------------------- * Postgres log access method interface * * TransactionLogFetch ! * TransactionLogUpdate * ---------------------------------------------------------------- */ --- 40,58 ---- /* Local functions */ static XidStatus TransactionLogFetch(TransactionId transactionId); /* ---------------------------------------------------------------- * Postgres log access method interface * * TransactionLogFetch ! * ! * Prior to 8.4, we also had TransactionLogUpdate and ! * TransactionLogMultiUpdate. These have now been merged ! * into a single command TransactionIdSetTreeStatus(), ! * though that is now part of clog.c because of the need ! * for closer integration with clog code to achieve ! * atomic clog updates for subtransactions. * ---------------------------------------------------------------- */ *************** *** 100,140 **** return xidstatus; } - /* - * TransactionLogUpdate - * - * Store the new status of a transaction. The commit record LSN must be - * passed when recording an async commit; else it should be InvalidXLogRecPtr. - */ - static inline void - TransactionLogUpdate(TransactionId transactionId, - XidStatus status, XLogRecPtr lsn) - { - /* - * update the commit log - */ - TransactionIdSetStatus(transactionId, status, lsn); - } - - /* - * TransactionLogMultiUpdate - * - * Update multiple transaction identifiers to a given status. - * Don't depend on this being atomic; it's not. - */ - static inline void - TransactionLogMultiUpdate(int nxids, TransactionId *xids, - XidStatus status, XLogRecPtr lsn) - { - int i; - - Assert(nxids != 0); - - for (i = 0; i < nxids; i++) - TransactionIdSetStatus(xids[i], status, lsn); - } - - /* ---------------------------------------------------------------- * Interface functions * --- 104,109 ---- *************** *** 143,154 **** * ======== * these functions test the transaction status of * a specified transaction id. ! * ! * TransactionIdCommit ! * TransactionIdAbort * ======== * these functions set the transaction status ! * of the specified xid. * * See also TransactionIdIsInProgress, which once was in this module * but now lives in procarray.c. --- 112,125 ---- * ======== * these functions test the transaction status of * a specified transaction id. ! * ! * TransactionIdCommitTree ! * TransactionIdAsyncCommitTree ! * TransactionIdAbortTree * ======== * these functions set the transaction status ! * of the specified transaction tree. As of 8.4, these ! * are now atomic so we set the whole tree in a single call. * * See also TransactionIdIsInProgress, which once was in this module * but now lives in procarray.c. *************** *** 287,374 **** return false; } - - /* - * TransactionIdCommit - * Commits the transaction associated with the identifier. - * - * Note: - * Assumes transaction identifier is valid. - */ - void - TransactionIdCommit(TransactionId transactionId) - { - TransactionLogUpdate(transactionId, TRANSACTION_STATUS_COMMITTED, - InvalidXLogRecPtr); - } - - /* - * TransactionIdAsyncCommit - * Same as above, but for async commits. The commit record LSN is needed. - */ - void - TransactionIdAsyncCommit(TransactionId transactionId, XLogRecPtr lsn) - { - TransactionLogUpdate(transactionId, TRANSACTION_STATUS_COMMITTED, lsn); - } - - /* - * TransactionIdAbort - * Aborts the transaction associated with the identifier. - * - * Note: - * Assumes transaction identifier is valid. - * No async version of this is needed. - */ - void - TransactionIdAbort(TransactionId transactionId) - { - TransactionLogUpdate(transactionId, TRANSACTION_STATUS_ABORTED, - InvalidXLogRecPtr); - } - - /* - * TransactionIdSubCommit - * Marks the subtransaction associated with the identifier as - * sub-committed. - * - * Note: - * No async version of this is needed. - */ - void - TransactionIdSubCommit(TransactionId transactionId) - { - TransactionLogUpdate(transactionId, TRANSACTION_STATUS_SUB_COMMITTED, - InvalidXLogRecPtr); - } - /* * TransactionIdCommitTree ! * Marks all the given transaction ids as committed. ! * ! * The caller has to be sure that this is used only to mark subcommitted ! * subtransactions as committed, and only *after* marking the toplevel ! * parent as committed. Otherwise there is a race condition against ! * TransactionIdDidCommit. */ void ! TransactionIdCommitTree(int nxids, TransactionId *xids) { ! if (nxids > 0) ! TransactionLogMultiUpdate(nxids, xids, TRANSACTION_STATUS_COMMITTED, ! InvalidXLogRecPtr); } /* * TransactionIdAsyncCommitTree ! * Same as above, but for async commits. The commit record LSN is needed. */ void ! TransactionIdAsyncCommitTree(int nxids, TransactionId *xids, XLogRecPtr lsn) { ! if (nxids > 0) ! TransactionLogMultiUpdate(nxids, xids, TRANSACTION_STATUS_COMMITTED, ! lsn); } /* --- 258,284 ---- return false; } /* * TransactionIdCommitTree ! * Marks all the given transaction ids as committed, atomically. */ void ! TransactionIdCommitTree(TransactionId xid, int nxids, TransactionId *xids) { ! return TransactionIdSetTreeStatus(xid, nxids, xids, ! TRANSACTION_STATUS_COMMITTED, InvalidXLogRecPtr); } /* * TransactionIdAsyncCommitTree ! * Same as above, but for async commits, atomically. The commit record ! * LSN is needed. */ void ! TransactionIdAsyncCommitTree(TransactionId xid, int nxids, TransactionId *xids, XLogRecPtr lsn) { ! return TransactionIdSetTreeStatus(xid, nxids, xids, ! TRANSACTION_STATUS_COMMITTED, lsn); } /* *************** *** 379,392 **** * will consider all the xacts as not-yet-committed anyway. */ void ! TransactionIdAbortTree(int nxids, TransactionId *xids) { ! if (nxids > 0) ! TransactionLogMultiUpdate(nxids, xids, TRANSACTION_STATUS_ABORTED, ! InvalidXLogRecPtr); } - /* * TransactionIdPrecedes --- is id1 logically < id2? */ --- 289,300 ---- * will consider all the xacts as not-yet-committed anyway. */ void ! TransactionIdAbortTree(TransactionId xid, int nxids, TransactionId *xids) { ! TransactionIdSetTreeStatus(xid, nxids, xids, ! TRANSACTION_STATUS_ABORTED, InvalidXLogRecPtr); } /* * TransactionIdPrecedes --- is id1 logically < id2? */ Index: src/backend/access/transam/twophase.c =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/backend/access/transam/twophase.c,v retrieving revision 1.45 diff -c -r1.45 twophase.c *** src/backend/access/transam/twophase.c 11 Aug 2008 11:05:10 -0000 1.45 --- src/backend/access/transam/twophase.c 24 Sep 2008 17:33:23 -0000 *************** *** 1745,1753 **** XLogFlush(recptr); /* Mark the transaction committed in pg_clog */ ! TransactionIdCommit(xid); ! /* to avoid race conditions, the parent must commit first */ ! TransactionIdCommitTree(nchildren, children); /* Checkpoint can proceed now */ MyProc->inCommit = false; --- 1745,1751 ---- XLogFlush(recptr); /* Mark the transaction committed in pg_clog */ ! TransactionIdCommitTree(xid, nchildren, children); /* Checkpoint can proceed now */ MyProc->inCommit = false; *************** *** 1822,1829 **** * Mark the transaction aborted in clog. This is not absolutely necessary * but we may as well do it while we are here. */ ! TransactionIdAbort(xid); ! TransactionIdAbortTree(nchildren, children); END_CRIT_SECTION(); } --- 1820,1826 ---- * Mark the transaction aborted in clog. This is not absolutely necessary * but we may as well do it while we are here. */ ! TransactionIdAbortTree(xid, nchildren, children); END_CRIT_SECTION(); } Index: src/backend/access/transam/xact.c =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/backend/access/transam/xact.c,v retrieving revision 1.265 diff -c -r1.265 xact.c *** src/backend/access/transam/xact.c 11 Aug 2008 11:05:10 -0000 1.265 --- src/backend/access/transam/xact.c 24 Sep 2008 17:33:23 -0000 *************** *** 254,260 **** static TransactionId RecordTransactionAbort(bool isSubXact); static void StartTransaction(void); - static void RecordSubTransactionCommit(void); static void StartSubTransaction(void); static void CommitSubTransaction(void); static void AbortSubTransaction(void); --- 254,259 ---- *************** *** 952,962 **** * Now we may update the CLOG, if we wrote a COMMIT record above */ if (markXidCommitted) ! { ! TransactionIdCommit(xid); ! /* to avoid race conditions, the parent must commit first */ ! TransactionIdCommitTree(nchildren, children); ! } } else { --- 951,957 ---- * Now we may update the CLOG, if we wrote a COMMIT record above */ if (markXidCommitted) ! TransactionIdCommitTree(xid, nchildren, children); } else { *************** *** 974,984 **** * flushed before the CLOG may be updated. */ if (markXidCommitted) ! { ! TransactionIdAsyncCommit(xid, XactLastRecEnd); ! /* to avoid race conditions, the parent must commit first */ ! TransactionIdAsyncCommitTree(nchildren, children, XactLastRecEnd); ! } } /* --- 969,975 ---- * flushed before the CLOG may be updated. */ if (markXidCommitted) ! TransactionIdAsyncCommitTree(xid, nchildren, children, XactLastRecEnd); } /* *************** *** 1156,1191 **** s->maxChildXids = 0; } - /* - * RecordSubTransactionCommit - */ - static void - RecordSubTransactionCommit(void) - { - TransactionId xid = GetCurrentTransactionIdIfAny(); - - /* - * We do not log the subcommit in XLOG; it doesn't matter until the - * top-level transaction commits. - * - * We must mark the subtransaction subcommitted in the CLOG if it had a - * valid XID assigned. If it did not, nobody else will ever know about - * the existence of this subxact. We don't have to deal with deletions - * scheduled for on-commit here, since they'll be reassigned to our parent - * (who might still abort). - */ - if (TransactionIdIsValid(xid)) - { - /* XXX does this really need to be a critical section? */ - START_CRIT_SECTION(); - - /* Record subtransaction subcommit */ - TransactionIdSubCommit(xid); - - END_CRIT_SECTION(); - } - } - /* ---------------------------------------------------------------- * AbortTransaction stuff * ---------------------------------------------------------------- --- 1147,1152 ---- *************** *** 1288,1301 **** * waiting for already-aborted subtransactions. It is OK to do it without * having flushed the ABORT record to disk, because in event of a crash * we'd be assumed to have aborted anyway. - * - * The ordering here isn't critical but it seems best to mark the parent - * first. This assures an atomic transition of all the subtransactions to - * aborted state from the point of view of concurrent - * TransactionIdDidAbort calls. */ ! TransactionIdAbort(xid); ! TransactionIdAbortTree(nchildren, children); END_CRIT_SECTION(); --- 1249,1256 ---- * waiting for already-aborted subtransactions. It is OK to do it without * having flushed the ABORT record to disk, because in event of a crash * we'd be assumed to have aborted anyway. */ ! TransactionIdAbortTree(xid, nchildren, children); END_CRIT_SECTION(); *************** *** 3791,3798 **** /* Must CCI to ensure commands of subtransaction are seen as done */ CommandCounterIncrement(); ! /* Mark subtransaction as subcommitted */ ! RecordSubTransactionCommit(); /* Post-commit cleanup */ if (TransactionIdIsValid(s->transactionId)) --- 3746,3757 ---- /* Must CCI to ensure commands of subtransaction are seen as done */ CommandCounterIncrement(); ! /* ! * Prior to 8.4 we marked subcommit in clog at this point. ! * We now only perform that step, if required, as part of the ! * atomic update of the whole transaction tree at top level ! * commit or abort. ! */ /* Post-commit cleanup */ if (TransactionIdIsValid(s->transactionId)) *************** *** 4259,4269 **** TransactionId max_xid; int i; - TransactionIdCommit(xid); - /* Mark committed subtransactions as committed */ sub_xids = (TransactionId *) &(xlrec->xnodes[xlrec->nrels]); ! TransactionIdCommitTree(xlrec->nsubxacts, sub_xids); /* Make sure nextXid is beyond any XID mentioned in the record */ max_xid = xid; --- 4218,4226 ---- TransactionId max_xid; int i; /* Mark committed subtransactions as committed */ sub_xids = (TransactionId *) &(xlrec->xnodes[xlrec->nrels]); ! TransactionIdCommitTree(xid, xlrec->nsubxacts, sub_xids); /* Make sure nextXid is beyond any XID mentioned in the record */ max_xid = xid; *************** *** 4299,4309 **** TransactionId max_xid; int i; - TransactionIdAbort(xid); - /* Mark subtransactions as aborted */ sub_xids = (TransactionId *) &(xlrec->xnodes[xlrec->nrels]); ! TransactionIdAbortTree(xlrec->nsubxacts, sub_xids); /* Make sure nextXid is beyond any XID mentioned in the record */ max_xid = xid; --- 4256,4264 ---- TransactionId max_xid; int i; /* Mark subtransactions as aborted */ sub_xids = (TransactionId *) &(xlrec->xnodes[xlrec->nrels]); ! TransactionIdAbortTree(xid, xlrec->nsubxacts, sub_xids); /* Make sure nextXid is beyond any XID mentioned in the record */ max_xid = xid; Index: src/include/access/clog.h =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/include/access/clog.h,v retrieving revision 1.21 diff -c -r1.21 clog.h *** src/include/access/clog.h 1 Jan 2008 19:45:56 -0000 1.21 --- src/include/access/clog.h 24 Sep 2008 17:33:23 -0000 *************** *** 32,38 **** #define NUM_CLOG_BUFFERS 8 ! extern void TransactionIdSetStatus(TransactionId xid, XidStatus status, XLogRecPtr lsn); extern XidStatus TransactionIdGetStatus(TransactionId xid, XLogRecPtr *lsn); extern Size CLOGShmemSize(void); --- 32,39 ---- #define NUM_CLOG_BUFFERS 8 ! extern void TransactionIdSetTreeStatus(TransactionId xid, int nsubxids, ! TransactionId *subxids, XidStatus status, XLogRecPtr lsn); extern XidStatus TransactionIdGetStatus(TransactionId xid, XLogRecPtr *lsn); extern Size CLOGShmemSize(void); Index: src/include/access/transam.h =================================================================== RCS file: /home/sriggs/pg/REPOSITORY/pgsql/src/include/access/transam.h,v retrieving revision 1.65 diff -c -r1.65 transam.h *** src/include/access/transam.h 11 Mar 2008 20:20:35 -0000 1.65 --- src/include/access/transam.h 24 Sep 2008 17:33:23 -0000 *************** *** 139,151 **** extern bool TransactionIdDidCommit(TransactionId transactionId); extern bool TransactionIdDidAbort(TransactionId transactionId); extern bool TransactionIdIsKnownCompleted(TransactionId transactionId); - extern void TransactionIdCommit(TransactionId transactionId); - extern void TransactionIdAsyncCommit(TransactionId transactionId, XLogRecPtr lsn); extern void TransactionIdAbort(TransactionId transactionId); ! extern void TransactionIdSubCommit(TransactionId transactionId); ! extern void TransactionIdCommitTree(int nxids, TransactionId *xids); ! extern void TransactionIdAsyncCommitTree(int nxids, TransactionId *xids, XLogRecPtr lsn); ! extern void TransactionIdAbortTree(int nxids, TransactionId *xids); extern bool TransactionIdPrecedes(TransactionId id1, TransactionId id2); extern bool TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2); extern bool TransactionIdFollows(TransactionId id1, TransactionId id2); --- 139,148 ---- extern bool TransactionIdDidCommit(TransactionId transactionId); extern bool TransactionIdDidAbort(TransactionId transactionId); extern bool TransactionIdIsKnownCompleted(TransactionId transactionId); extern void TransactionIdAbort(TransactionId transactionId); ! extern void TransactionIdCommitTree(TransactionId xid, int nxids, TransactionId *xids); ! extern void TransactionIdAsyncCommitTree(TransactionId xid, int nxids, TransactionId *xids, XLogRecPtr lsn); ! extern void TransactionIdAbortTree(TransactionId xid, int nxids, TransactionId *xids); extern bool TransactionIdPrecedes(TransactionId id1, TransactionId id2); extern bool TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2); extern bool TransactionIdFollows(TransactionId id1, TransactionId id2); -- Sent via pgsql-patches mailing list (pgsql-patches@...) 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