diff options
Diffstat (limited to 'src/backend/access/heap')
| -rw-r--r-- | src/backend/access/heap/README.HOT | 10 | ||||
| -rw-r--r-- | src/backend/access/heap/heapam.c | 4 | ||||
| -rw-r--r-- | src/backend/access/heap/heapam_handler.c | 2 | ||||
| -rw-r--r-- | src/backend/access/heap/pruneheap.c | 10 | ||||
| -rw-r--r-- | src/backend/access/heap/vacuumlazy.c | 6 |
5 files changed, 16 insertions, 16 deletions
diff --git a/src/backend/access/heap/README.HOT b/src/backend/access/heap/README.HOT index 4cf3c3a0d4c..68c6709aa88 100644 --- a/src/backend/access/heap/README.HOT +++ b/src/backend/access/heap/README.HOT @@ -149,8 +149,8 @@ the descendant heap-only tuple. It is conceivable that someone prunes the heap-only tuple before that, and even conceivable that the line pointer is re-used for another purpose. Therefore, when following a HOT chain, it is always necessary to be prepared for the possibility that the -linked-to item pointer is unused, dead, or redirected; and if it is a -normal item pointer, we still have to check that XMIN of the tuple matches +linked-to line pointer is unused, dead, or redirected; and if it is a +normal line pointer, we still have to check that XMIN of the tuple matches the XMAX of the tuple we left. Otherwise we should assume that we have come to the end of the HOT chain. Note that this sort of XMIN/XMAX matching is required when following ordinary update chains anyway. @@ -171,14 +171,14 @@ bit: there can be at most one visible tuple in the chain, so we can stop when we find it. This rule does not work for non-MVCC snapshots, though.) Sequential scans do not need to pay attention to the HOT links because -they scan every item pointer on the page anyway. The same goes for a +they scan every line pointer on the page anyway. The same goes for a bitmap heap scan with a lossy bitmap. Pruning ------- -HOT pruning means updating item pointers so that HOT chains are +HOT pruning means updating line pointers so that HOT chains are reduced in length, by collapsing out line pointers for intermediate dead tuples. Although this makes those line pointers available for re-use, it does not immediately make the space occupied by their tuples available. @@ -271,7 +271,7 @@ physical tuple by eliminating an intermediate heap-only tuple or replacing a physical root tuple by a redirect pointer, a decrement in the table's number of dead tuples is reported to pgstats, which may postpone autovacuuming. Note that we do not count replacing a root tuple -by a DEAD item pointer as decrementing n_dead_tuples; we still want +by a DEAD line pointer as decrementing n_dead_tuples; we still want autovacuum to run to clean up the index entries and DEAD item. This area probably needs further work ... diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 6f26ddac5f9..d97cb4c6426 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -7163,7 +7163,7 @@ log_heap_clean(Relation reln, Buffer buffer, * arrays need not be stored too. Note that even if all three arrays are * empty, we want to expose the buffer as a candidate for whole-page * storage, since this record type implies a defragmentation operation - * even if no item pointers changed state. + * even if no line pointers changed state. */ if (nredirected > 0) XLogRegisterBufData(0, (char *) redirected, @@ -7724,7 +7724,7 @@ heap_xlog_clean(XLogReaderState *record) nunused = (end - nowunused); Assert(nunused >= 0); - /* Update all item pointers per the record, and repair fragmentation */ + /* Update all line pointers per the record, and repair fragmentation */ heap_page_prune_execute(buffer, redirected, nredirected, nowdead, ndead, diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c index 4d179881f27..bc47856ad53 100644 --- a/src/backend/access/heap/heapam_handler.c +++ b/src/backend/access/heap/heapam_handler.c @@ -2162,7 +2162,7 @@ heapam_scan_bitmap_next_block(TableScanDesc scan, else { /* - * Bitmap is lossy, so we must examine each item pointer on the page. + * Bitmap is lossy, so we must examine each line pointer on the page. * But we can ignore HOT chains, since we'll check each tuple anyway. */ Page dp = (Page) BufferGetPage(buffer); diff --git a/src/backend/access/heap/pruneheap.c b/src/backend/access/heap/pruneheap.c index a3e51922d85..417a2bf8e6e 100644 --- a/src/backend/access/heap/pruneheap.c +++ b/src/backend/access/heap/pruneheap.c @@ -324,7 +324,7 @@ heap_page_prune(Relation relation, Buffer buffer, TransactionId OldestXmin, /* - * Prune specified item pointer or a HOT chain originating at that item. + * Prune specified line pointer or a HOT chain originating at line pointer. * * If the item is an index-referenced tuple (i.e. not a heap-only tuple), * the HOT chain is pruned by removing all DEAD tuples at the start of the HOT @@ -454,7 +454,7 @@ heap_prune_chain(Relation relation, Buffer buffer, OffsetNumber rootoffnum, } /* - * Likewise, a dead item pointer can't be part of the chain. (We + * Likewise, a dead line pointer can't be part of the chain. (We * already eliminated the case of dead root tuple outside this * function.) */ @@ -630,7 +630,7 @@ heap_prune_record_prunable(PruneState *prstate, TransactionId xid) prstate->new_prune_xid = xid; } -/* Record item pointer to be redirected */ +/* Record line pointer to be redirected */ static void heap_prune_record_redirect(PruneState *prstate, OffsetNumber offnum, OffsetNumber rdoffnum) @@ -645,7 +645,7 @@ heap_prune_record_redirect(PruneState *prstate, prstate->marked[rdoffnum] = true; } -/* Record item pointer to be marked dead */ +/* Record line pointer to be marked dead */ static void heap_prune_record_dead(PruneState *prstate, OffsetNumber offnum) { @@ -656,7 +656,7 @@ heap_prune_record_dead(PruneState *prstate, OffsetNumber offnum) prstate->marked[offnum] = true; } -/* Record item pointer to be marked unused */ +/* Record line pointer to be marked unused */ static void heap_prune_record_unused(PruneState *prstate, OffsetNumber offnum) { diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index f1a79059cdb..9e17acc110e 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -509,7 +509,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, live_tuples, /* live tuples (reltuples estimate) */ tups_vacuumed, /* tuples cleaned up by vacuum */ nkeep, /* dead-but-not-removable tuples */ - nunused; /* unused item pointers */ + nunused; /* unused line pointers */ IndexBulkDeleteResult **indstats; int i; PGRUsage ru0; @@ -1017,7 +1017,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, ItemPointerSet(&(tuple.t_self), blkno, offnum); /* - * DEAD item pointers are to be vacuumed normally; but we don't + * DEAD line pointers are to be vacuumed normally; but we don't * count them in tups_vacuumed, else we'd be double-counting (at * least in the common case where heap_page_prune() just freed up * a non-HOT tuple). @@ -1483,7 +1483,7 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats, appendStringInfo(&buf, _("%.0f dead row versions cannot be removed yet, oldest xmin: %u\n"), nkeep, OldestXmin); - appendStringInfo(&buf, _("There were %.0f unused item pointers.\n"), + appendStringInfo(&buf, _("There were %.0f unused item identifiers.\n"), nunused); appendStringInfo(&buf, ngettext("Skipped %u page due to buffer pins, ", "Skipped %u pages due to buffer pins, ", |