diff options
Diffstat (limited to 'src/backend/access/heap/heapam_handler.c')
| -rw-r--r-- | src/backend/access/heap/heapam_handler.c | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c index 58de2c82a70..cc4d51d5514 100644 --- a/src/backend/access/heap/heapam_handler.c +++ b/src/backend/access/heap/heapam_handler.c @@ -1055,33 +1055,36 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap, } /* - * Prepare to analyze block `blockno` of `scan`. The scan has been started + * Prepare to analyze the next block in the read stream. Returns false if + * the stream is exhausted and true otherwise. The scan must have been started * with SO_TYPE_ANALYZE option. * * This routine holds a buffer pin and lock on the heap page. They are held * until heapam_scan_analyze_next_tuple() returns false. That is until all the * items of the heap page are analyzed. */ -void -heapam_scan_analyze_next_block(TableScanDesc scan, BlockNumber blockno, - BufferAccessStrategy bstrategy) +bool +heapam_scan_analyze_next_block(TableScanDesc scan, ReadStream *stream) { HeapScanDesc hscan = (HeapScanDesc) scan; /* * We must maintain a pin on the target page's buffer to ensure that * concurrent activity - e.g. HOT pruning - doesn't delete tuples out from - * under us. Hence, pin the page until we are done looking at it. We - * also choose to hold sharelock on the buffer throughout --- we could - * release and re-acquire sharelock for each tuple, but since we aren't - * doing much work per tuple, the extra lock traffic is probably better - * avoided. + * under us. It comes from the stream already pinned. We also choose to + * hold sharelock on the buffer throughout --- we could release and + * re-acquire sharelock for each tuple, but since we aren't doing much + * work per tuple, the extra lock traffic is probably better avoided. */ - hscan->rs_cblock = blockno; - hscan->rs_cindex = FirstOffsetNumber; - hscan->rs_cbuf = ReadBufferExtended(scan->rs_rd, MAIN_FORKNUM, - blockno, RBM_NORMAL, bstrategy); + hscan->rs_cbuf = read_stream_next_buffer(stream, NULL); + if (!BufferIsValid(hscan->rs_cbuf)) + return false; + LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE); + + hscan->rs_cblock = BufferGetBlockNumber(hscan->rs_cbuf); + hscan->rs_cindex = FirstOffsetNumber; + return true; } /* |