diff options
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/access/common/tidstore.c | 63 | ||||
| -rw-r--r-- | src/backend/access/heap/vacuumlazy.c | 9 |
2 files changed, 36 insertions, 36 deletions
diff --git a/src/backend/access/common/tidstore.c b/src/backend/access/common/tidstore.c index fb3949d69f6..a7179759d67 100644 --- a/src/backend/access/common/tidstore.c +++ b/src/backend/access/common/tidstore.c @@ -147,9 +147,6 @@ struct TidStoreIter TidStoreIterResult output; }; -static void tidstore_iter_extract_tids(TidStoreIter *iter, BlockNumber blkno, - BlocktableEntry *page); - /* * Create a TidStore. The TidStore will live in the memory context that is * CurrentMemoryContext at the time of this call. The TID storage, backed @@ -486,13 +483,6 @@ TidStoreBeginIterate(TidStore *ts) iter = palloc0(sizeof(TidStoreIter)); iter->ts = ts; - /* - * We start with an array large enough to contain at least the offsets - * from one completely full bitmap element. - */ - iter->output.max_offset = 2 * BITS_PER_BITMAPWORD; - iter->output.offsets = palloc(sizeof(OffsetNumber) * iter->output.max_offset); - if (TidStoreIsShared(ts)) iter->tree_iter.shared = shared_ts_begin_iterate(ts->tree.shared); else @@ -503,9 +493,9 @@ TidStoreBeginIterate(TidStore *ts) /* - * Scan the TidStore and return the TIDs of the next block. The offsets in - * each iteration result are ordered, as are the block numbers over all - * iterations. + * Return a result that contains the next block number and that can be used to + * obtain the set of offsets by calling TidStoreGetBlockOffsets(). The result + * is copyable. */ TidStoreIterResult * TidStoreIterateNext(TidStoreIter *iter) @@ -521,8 +511,8 @@ TidStoreIterateNext(TidStoreIter *iter) if (page == NULL) return NULL; - /* Collect TIDs from the key-value pair */ - tidstore_iter_extract_tids(iter, (BlockNumber) key, page); + iter->output.blkno = key; + iter->output.internal_page = page; return &(iter->output); } @@ -540,7 +530,6 @@ TidStoreEndIterate(TidStoreIter *iter) else local_ts_end_iterate(iter->tree_iter.local); - pfree(iter->output.offsets); pfree(iter); } @@ -575,24 +564,32 @@ TidStoreGetHandle(TidStore *ts) return (dsa_pointer) shared_ts_get_handle(ts->tree.shared); } -/* Extract TIDs from the given key-value pair */ -static void -tidstore_iter_extract_tids(TidStoreIter *iter, BlockNumber blkno, - BlocktableEntry *page) +/* + * Given a TidStoreIterResult returned by TidStoreIterateNext(), extract the + * offset numbers. Returns the number of offsets filled in, if <= + * max_offsets. Otherwise, fills in as much as it can in the given space, and + * returns the size of the buffer that would be needed. + */ +int +TidStoreGetBlockOffsets(TidStoreIterResult *result, + OffsetNumber *offsets, + int max_offsets) { - TidStoreIterResult *result = (&iter->output); + BlocktableEntry *page = result->internal_page; + int num_offsets = 0; int wordnum; - result->num_offsets = 0; - result->blkno = blkno; - if (page->header.nwords == 0) { /* we have offsets in the header */ for (int i = 0; i < NUM_FULL_OFFSETS; i++) { if (page->header.full_offsets[i] != InvalidOffsetNumber) - result->offsets[result->num_offsets++] = page->header.full_offsets[i]; + { + if (num_offsets < max_offsets) + offsets[num_offsets] = page->header.full_offsets[i]; + num_offsets++; + } } } else @@ -602,21 +599,19 @@ tidstore_iter_extract_tids(TidStoreIter *iter, BlockNumber blkno, bitmapword w = page->words[wordnum]; int off = wordnum * BITS_PER_BITMAPWORD; - /* Make sure there is enough space to add offsets */ - if ((result->num_offsets + BITS_PER_BITMAPWORD) > result->max_offset) - { - result->max_offset *= 2; - result->offsets = repalloc(result->offsets, - sizeof(OffsetNumber) * result->max_offset); - } - while (w != 0) { if (w & 1) - result->offsets[result->num_offsets++] = (OffsetNumber) off; + { + if (num_offsets < max_offsets) + offsets[num_offsets] = (OffsetNumber) off; + num_offsets++; + } off++; w >>= 1; } } } + + return num_offsets; } diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index abb47ae5960..835b53415d0 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -2126,12 +2126,17 @@ lazy_vacuum_heap_rel(LVRelState *vacrel) Buffer buf; Page page; Size freespace; + OffsetNumber offsets[MaxOffsetNumber]; + int num_offsets; vacuum_delay_point(); blkno = iter_result->blkno; vacrel->blkno = blkno; + num_offsets = TidStoreGetBlockOffsets(iter_result, offsets, lengthof(offsets)); + Assert(num_offsets <= lengthof(offsets)); + /* * Pin the visibility map page in case we need to mark the page * all-visible. In most cases this will be very cheap, because we'll @@ -2143,8 +2148,8 @@ lazy_vacuum_heap_rel(LVRelState *vacrel) buf = ReadBufferExtended(vacrel->rel, MAIN_FORKNUM, blkno, RBM_NORMAL, vacrel->bstrategy); LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE); - lazy_vacuum_heap_page(vacrel, blkno, buf, iter_result->offsets, - iter_result->num_offsets, vmbuffer); + lazy_vacuum_heap_page(vacrel, blkno, buf, offsets, + num_offsets, vmbuffer); /* Now that we've vacuumed the page, record its available space */ page = BufferGetPage(buf); |