diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/access/heap/pruneheap.c | 49 | ||||
| -rw-r--r-- | src/backend/access/heap/vacuumlazy.c | 3 | ||||
| -rw-r--r-- | src/include/access/heapam.h | 1 |
3 files changed, 40 insertions, 13 deletions
diff --git a/src/backend/access/heap/pruneheap.c b/src/backend/access/heap/pruneheap.c index 47b9e209154..c2c20d4b3bc 100644 --- a/src/backend/access/heap/pruneheap.c +++ b/src/backend/access/heap/pruneheap.c @@ -33,7 +33,8 @@ typedef struct { Relation rel; - /* tuple visibility test, initialized for the relation */ + /* State used to test tuple visibility; Initialized for the relation */ + TransactionId oldest_xmin; GlobalVisState *vistest; /* @@ -205,7 +206,8 @@ heap_page_prune_opt(Relation relation, Buffer buffer) int ndeleted, nnewlpdead; - ndeleted = heap_page_prune(relation, buffer, vistest, limited_xmin, + ndeleted = heap_page_prune(relation, buffer, InvalidTransactionId, + vistest, limited_xmin, limited_ts, &nnewlpdead, NULL); /* @@ -247,11 +249,14 @@ heap_page_prune_opt(Relation relation, Buffer buffer) * also need to account for a reduction in the length of the line pointer * array following array truncation by us. * - * vistest is used to distinguish whether tuples are DEAD or RECENTLY_DEAD - * (see heap_prune_satisfies_vacuum and - * HeapTupleSatisfiesVacuum). old_snap_xmin / old_snap_ts need to - * either have been set by TransactionIdLimitedForOldSnapshots, or - * InvalidTransactionId/0 respectively. + * vistest and oldest_xmin are used to distinguish whether tuples are DEAD or + * RECENTLY_DEAD (see heap_prune_satisfies_vacuum and + * HeapTupleSatisfiesVacuum). If oldest_xmin is provided by the caller, it is + * used before consulting GlobalVisState. + * + * old_snap_xmin / old_snap_ts need to either have been set by + * TransactionIdLimitedForOldSnapshots, or InvalidTransactionId/0 + * respectively. * * Sets *nnewlpdead for caller, indicating the number of items that were * newly set LP_DEAD during prune operation. @@ -263,6 +268,7 @@ heap_page_prune_opt(Relation relation, Buffer buffer) */ int heap_page_prune(Relation relation, Buffer buffer, + TransactionId oldest_xmin, GlobalVisState *vistest, TransactionId old_snap_xmin, TimestampTz old_snap_ts, @@ -290,6 +296,7 @@ heap_page_prune(Relation relation, Buffer buffer, */ prstate.new_prune_xid = InvalidTransactionId; prstate.rel = relation; + prstate.oldest_xmin = oldest_xmin; prstate.vistest = vistest; prstate.old_snap_xmin = old_snap_xmin; prstate.old_snap_ts = old_snap_ts; @@ -520,13 +527,31 @@ heap_prune_satisfies_vacuum(PruneState *prstate, HeapTuple tup, Buffer buffer) } /* - * First check if GlobalVisTestIsRemovableXid() is sufficient to find the - * row dead. If not, and old_snapshot_threshold is enabled, try to use the - * lowered horizon. + * For VACUUM, we must be sure to prune tuples with xmax older than + * oldest_xmin -- a visibility cutoff determined at the beginning of + * vacuuming the relation. oldest_xmin is used for freezing determination + * and we cannot freeze dead tuples' xmaxes. + */ + if (TransactionIdIsValid(prstate->oldest_xmin) && + NormalTransactionIdPrecedes(dead_after, prstate->oldest_xmin)) + return HEAPTUPLE_DEAD; + + /* + * Determine whether or not the tuple is considered dead when compared + * with the provided GlobalVisState. On-access pruning does not provide + * oldest_xmin. And for vacuum, even if the tuple's xmax is not older than + * oldest_xmin, GlobalVisTestIsRemovableXid() could find the row dead if + * the GlobalVisState has been updated since the beginning of vacuuming + * the relation. */ if (GlobalVisTestIsRemovableXid(prstate->vistest, dead_after)) - res = HEAPTUPLE_DEAD; - else if (OldSnapshotThresholdActive()) + return HEAPTUPLE_DEAD; + + /* + * If GlobalVisTestIsRemovableXid() is not sufficient to find the row dead + * and old_snapshot_threshold is enabled, try to use the lowered horizon. + */ + if (OldSnapshotThresholdActive()) { /* haven't determined limited horizon yet, requests */ if (!TransactionIdIsValid(prstate->old_snap_xmin)) diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index c474b061146..9fa88960ada 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -1581,7 +1581,8 @@ retry: * lpdead_items's final value can be thought of as the number of tuples * that were deleted from indexes. */ - tuples_deleted = heap_page_prune(rel, buf, vacrel->vistest, + tuples_deleted = heap_page_prune(rel, buf, vacrel->cutoffs.OldestXmin, + vacrel->vistest, InvalidTransactionId, 0, &nnewlpdead, &vacrel->offnum); diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h index faf50265191..c7278219b24 100644 --- a/src/include/access/heapam.h +++ b/src/include/access/heapam.h @@ -285,6 +285,7 @@ extern TransactionId heap_index_delete_tuples(Relation rel, struct GlobalVisState; extern void heap_page_prune_opt(Relation relation, Buffer buffer); extern int heap_page_prune(Relation relation, Buffer buffer, + TransactionId oldest_xmin, struct GlobalVisState *vistest, TransactionId old_snap_xmin, TimestampTz old_snap_ts, |