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Remove pointless HeapTupleHeaderIndicatesMovedPartitions calls

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Pavan Deolasee recently noted that a few of the
HeapTupleHeaderIndicatesMovedPartitions calls added by commit
5db6df0c01 are useless, since they are done after comparing t_self
with t_ctid.  But because t_self can never be set to the magical values
that indicate that the tuple moved partition, this can never succeed: if
the first test fails (so we know t_self equals t_ctid), necessarily the
second test will also fail.

So these checks can be removed and no harm is done.

Discussion: https://postgr.es/m/20200929164411.GA15497@alvherre.pgsql
This commit is contained in:
Alvaro Herrera 2020-10-15 14:32:34 -03:00
parent 2203ede9ae
commit 85adb5e91e
2 changed files with 7 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/access/heap/heapam.c
View File

@ -2618,8 +2618,7 @@ l1:
HEAP_XMAX_IS_LOCKED_ONLY(tp.t_data->t_infomask) ||
HeapTupleHeaderIsOnlyLocked(tp.t_data))
result = TM_Ok;
else if (!ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tp.t_data))
else if (!ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid))
result = TM_Updated;
else
result = TM_Deleted;
@ -3248,8 +3247,7 @@ l2:
if (can_continue)
result = TM_Ok;
else if (!ItemPointerEquals(&oldtup.t_self, &oldtup.t_data->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(oldtup.t_data))
else if (!ItemPointerEquals(&oldtup.t_self, &oldtup.t_data->t_ctid))
result = TM_Updated;
else
result = TM_Deleted;
@ -4485,8 +4483,7 @@ l3:
HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask) ||
HeapTupleHeaderIsOnlyLocked(tuple->t_data))
result = TM_Ok;
else if (!ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tuple->t_data))
else if (!ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid))
result = TM_Updated;
else
result = TM_Deleted;
@ -5059,8 +5056,7 @@ test_lockmode_for_conflict(MultiXactStatus status, TransactionId xid,
LOCKMODE_from_mxstatus(wantedstatus)))
{
/* bummer */
if (!ItemPointerEquals(&tup->t_self, &tup->t_data->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tup->t_data))
if (!ItemPointerEquals(&tup->t_self, &tup->t_data->t_ctid))
return TM_Updated;
else
return TM_Deleted;

9
src/backend/access/heap/heapam_visibility.c
View File

@ -607,8 +607,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
{
if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
return TM_Ok;
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tuple))
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid))
return TM_Updated; /* updated by other */
else
return TM_Deleted; /* deleted by other */
@ -653,8 +652,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
if (TransactionIdDidCommit(xmax))
{
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tuple))
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid))
return TM_Updated;
else
return TM_Deleted;
@ -714,8 +712,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
HeapTupleHeaderGetRawXmax(tuple));
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid) ||
HeapTupleHeaderIndicatesMovedPartitions(tuple))
if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid))
return TM_Updated; /* updated by other */
else
return TM_Deleted; /* deleted by other */