mirror of
https://github.com/postgres/postgres.git
synced 2025-05-17 06:41:24 +03:00
Adjust time qual checking code so that we always check TransactionIdIsInProgress
before we check commit/abort status. Formerly this was done in some paths but not all, with the result that a transaction might be considered committed for some purposes before it became committed for others. Per example found by Jan Wieck.
This commit is contained in:
Tom Lane
parent
26f64e4c7a
commit
501ec7b64c
@ -11,12 +11,26 @@
|
||||
* containing the tuple. (VACUUM FULL assumes it's sufficient to have
|
||||
* exclusive lock on the containing relation, instead.)
|
||||
*
|
||||
* NOTE: must check TransactionIdIsInProgress (which looks in PGPROC array)
|
||||
* before TransactionIdDidCommit/TransactionIdDidAbort (which look in
|
||||
* pg_clog). Otherwise we have a race condition: we might decide that a
|
||||
* just-committed transaction crashed, because none of the tests succeed.
|
||||
* xact.c is careful to record commit/abort in pg_clog before it unsets
|
||||
* MyProc->xid in PGPROC array. That fixes that problem, but it also
|
||||
* means there is a window where TransactionIdIsInProgress and
|
||||
* TransactionIdDidCommit will both return true. If we check only
|
||||
* TransactionIdDidCommit, we could consider a tuple committed when a
|
||||
* later GetSnapshotData call will still think the originating transaction
|
||||
* is in progress, which leads to application-level inconsistency. The
|
||||
* upshot is that we gotta check TransactionIdIsInProgress first in all
|
||||
* code paths.
|
||||
*
|
||||
*
|
||||
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/time/tqual.c,v 1.70 2003/10/01 21:30:52 tgl Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/time/tqual.c,v 1.70.2.1 2005/05/07 21:23:02 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -122,14 +136,16 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple)
|
||||
|
||||
return false;
|
||||
}
|
||||
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple)))
|
||||
return false;
|
||||
else if (TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
else
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return false;
|
||||
}
|
||||
else
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
}
|
||||
|
||||
/* by here, the inserting transaction has committed */
|
||||
@ -151,10 +167,13 @@ HeapTupleSatisfiesItself(HeapTupleHeader tuple)
|
||||
return false;
|
||||
}
|
||||
|
||||
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
|
||||
return true;
|
||||
|
||||
if (!TransactionIdDidCommit(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID;
|
||||
return true;
|
||||
}
|
||||
|
||||
@ -271,14 +290,16 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple)
|
||||
else
|
||||
return false; /* deleted before scan started */
|
||||
}
|
||||
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple)))
|
||||
return false;
|
||||
else if (TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
else
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return false;
|
||||
}
|
||||
else
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
}
|
||||
|
||||
/* by here, the inserting transaction has committed */
|
||||
@ -303,10 +324,13 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple)
|
||||
return false; /* deleted before scan started */
|
||||
}
|
||||
|
||||
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
|
||||
return true;
|
||||
|
||||
if (!TransactionIdDidCommit(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID;
|
||||
return true;
|
||||
}
|
||||
|
||||
@ -453,14 +477,16 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid)
|
||||
return HeapTupleInvisible; /* updated before scan
|
||||
* started */
|
||||
}
|
||||
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple)))
|
||||
return HeapTupleInvisible;
|
||||
else if (TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
else
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return HeapTupleInvisible;
|
||||
}
|
||||
else
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
}
|
||||
|
||||
/* by here, the inserting transaction has committed */
|
||||
@ -486,15 +512,14 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid)
|
||||
return HeapTupleInvisible; /* updated before scan started */
|
||||
}
|
||||
|
||||
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
|
||||
return HeapTupleBeingUpdated;
|
||||
|
||||
if (!TransactionIdDidCommit(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID; /* aborted */
|
||||
return HeapTupleMayBeUpdated;
|
||||
}
|
||||
/* running xact */
|
||||
return HeapTupleBeingUpdated; /* in updation by other */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID;
|
||||
return HeapTupleMayBeUpdated;
|
||||
}
|
||||
|
||||
/* xmax transaction committed */
|
||||
@ -582,19 +607,20 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple)
|
||||
|
||||
return false;
|
||||
}
|
||||
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(tuple)))
|
||||
{
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return false;
|
||||
}
|
||||
SnapshotDirty->xmin = HeapTupleHeaderGetXmin(tuple);
|
||||
/* XXX shouldn't we fall through to look at xmax? */
|
||||
return true; /* in insertion by other */
|
||||
}
|
||||
else
|
||||
else if (TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
else
|
||||
{
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
/* by here, the inserting transaction has committed */
|
||||
@ -617,16 +643,17 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple)
|
||||
return false;
|
||||
}
|
||||
|
||||
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
SnapshotDirty->xmax = HeapTupleHeaderGetXmax(tuple);
|
||||
return true;
|
||||
}
|
||||
|
||||
if (!TransactionIdDidCommit(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID; /* aborted */
|
||||
return true;
|
||||
}
|
||||
/* running xact */
|
||||
SnapshotDirty->xmax = HeapTupleHeaderGetXmax(tuple);
|
||||
return true; /* in updation by other */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID;
|
||||
return true;
|
||||
}
|
||||
|
||||
/* xmax transaction committed */
|
||||
@ -722,14 +749,16 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot)
|
||||
else
|
||||
return false; /* deleted before scan started */
|
||||
}
|
||||
else if (!TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple)))
|
||||
return false;
|
||||
else if (TransactionIdDidCommit(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
else
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMIN_INVALID;
|
||||
return false;
|
||||
}
|
||||
else
|
||||
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -769,10 +798,13 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot)
|
||||
return false; /* deleted before scan started */
|
||||
}
|
||||
|
||||
if (TransactionIdIsInProgress(HeapTupleHeaderGetXmax(tuple)))
|
||||
return true;
|
||||
|
||||
if (!TransactionIdDidCommit(HeapTupleHeaderGetXmax(tuple)))
|
||||
{
|
||||
if (TransactionIdDidAbort(HeapTupleHeaderGetXmax(tuple)))
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID; /* aborted */
|
||||
/* it must have aborted or crashed */
|
||||
tuple->t_infomask |= HEAP_XMAX_INVALID;
|
||||
return true;
|
||||
}
|
||||
|
||||
@ -821,13 +853,6 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin)
|
||||
*
|
||||
* If the inserting transaction aborted, then the tuple was never visible
|
||||
* to any other transaction, so we can delete it immediately.
|
||||
*
|
||||
* NOTE: must check TransactionIdIsInProgress (which looks in PROC array)
|
||||
* before TransactionIdDidCommit/TransactionIdDidAbort (which look in
|
||||
* pg_clog). Otherwise we have a race condition where we might decide
|
||||
* that a just-committed transaction crashed, because none of the
|
||||
* tests succeed. xact.c is careful to record commit/abort in pg_clog
|
||||
* before it unsets MyProc->xid in PROC array.
|
||||
*/
|
||||
if (!(tuple->t_infomask & HEAP_XMIN_COMMITTED))
|
||||
{
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user