postgres.git / summary / log / commit / refs

commit    85adb5e91ec2f45a388bef7a92a3d988c7e45501
Author:   Alvaro Herrera <alvherre@alvh.no-ip.org>
Date:     Thu Oct 15 17:32:34 2020 +0000

    Remove pointless HeapTupleHeaderIndicatesMovedPartitions calls
    
    Pavan Deolasee recently noted that a few of the
    HeapTupleHeaderIndicatesMovedPartitions calls added by commit
    5db6df0c0117 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


src/backend/access/heap/heapam.c | 12 ++++-------- src/backend/access/heap/heapam_visibility.c | 9 +++------ 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 1585861a021..868ff134539 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -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; diff --git a/src/backend/access/heap/heapam_visibility.c b/src/backend/access/heap/heapam_visibility.c index 80bd4940769..cab6a48a5da 100644 --- a/src/backend/access/heap/heapam_visibility.c +++ b/src/backend/access/heap/heapam_visibility.c @@ -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 */ [parent: 2203ede9ae85]