Revert "Avoid creation of the free space map for small heap relations."

This reverts commit ac88d2962a.

src/backend/access/brin/brin.c

@@ -1150,7 +1150,7 @@ terminate_brin_buildstate(BrinBuildState *state)
 		freespace = PageGetFreeSpace(page);
 		blk = BufferGetBlockNumber(state->bs_currentInsertBuf);
 		ReleaseBuffer(state->bs_currentInsertBuf);
-		RecordPageWithFreeSpace(state->bs_irel, blk, freespace, InvalidBlockNumber);
+		RecordPageWithFreeSpace(state->bs_irel, blk, freespace);
 		FreeSpaceMapVacuumRange(state->bs_irel, blk, blk + 1);
 	}
 

src/backend/access/brin/brin_pageops.c

@@ -310,7 +310,7 @@ brin_doupdate(Relation idxrel, BlockNumber pagesPerRange,
 
 		if (extended)
 		{
-			RecordPageWithFreeSpace(idxrel, newblk, freespace, InvalidBlockNumber);
+			RecordPageWithFreeSpace(idxrel, newblk, freespace);
 			FreeSpaceMapVacuumRange(idxrel, newblk, newblk + 1);
 		}
 
@@ -461,7 +461,7 @@ brin_doinsert(Relation idxrel, BlockNumber pagesPerRange,
 
 	if (extended)
 	{
-		RecordPageWithFreeSpace(idxrel, blk, freespace, InvalidBlockNumber);
+		RecordPageWithFreeSpace(idxrel, blk, freespace);
 		FreeSpaceMapVacuumRange(idxrel, blk, blk + 1);
 	}
 
@@ -654,7 +654,7 @@ brin_page_cleanup(Relation idxrel, Buffer buf)
 
 	/* Measure free space and record it */
 	RecordPageWithFreeSpace(idxrel, BufferGetBlockNumber(buf),
-							br_page_get_freespace(page), InvalidBlockNumber);
+							br_page_get_freespace(page));
 }
 
 /*
@@ -703,7 +703,7 @@ brin_getinsertbuffer(Relation irel, Buffer oldbuf, Size itemsz,
 	/* Choose initial target page, re-using existing target if known */
 	newblk = RelationGetTargetBlock(irel);
 	if (newblk == InvalidBlockNumber)
-		newblk = GetPageWithFreeSpace(irel, itemsz, true);
+		newblk = GetPageWithFreeSpace(irel, itemsz);
 
 	/*
 	 * Loop until we find a page with sufficient free space.  By the time we
@@ -895,7 +895,7 @@ brin_initialize_empty_new_buffer(Relation idxrel, Buffer buffer)
 	 * pages whose FSM records were forgotten in a crash.
 	 */
 	RecordPageWithFreeSpace(idxrel, BufferGetBlockNumber(buffer),
-							br_page_get_freespace(page), InvalidBlockNumber);
+							br_page_get_freespace(page));
 }
 
 

src/backend/access/heap/hio.c

@@ -239,14 +239,8 @@ RelationAddExtraBlocks(Relation relation, BulkInsertState bistate)
 		 * Immediately update the bottom level of the FSM.  This has a good
 		 * chance of making this page visible to other concurrently inserting
 		 * backends, and we want that to happen without delay.
-		 *
-		 * Since we know the table will end up with extraBlocks additional
-		 * pages, we pass the final number to avoid possible unnecessary
-		 * system calls and to make sure the FSM is created when we add the
-		 * first new page.
 		 */
-		RecordPageWithFreeSpace(relation, blockNum, freespace,
-								firstBlock + extraBlocks);
+		RecordPageWithFreeSpace(relation, blockNum, freespace);
 	}
 	while (--extraBlocks > 0);
 
@@ -383,9 +377,20 @@ RelationGetBufferForTuple(Relation relation, Size len,
 		 * We have no cached target page, so ask the FSM for an initial
 		 * target.
 		 */
-		targetBlock = GetPageWithFreeSpace(relation,
-										   len + saveFreeSpace,
-										   false);
+		targetBlock = GetPageWithFreeSpace(relation, len + saveFreeSpace);
+
+		/*
+		 * If the FSM knows nothing of the rel, try the last page before we
+		 * give up and extend.  This avoids one-tuple-per-page syndrome during
+		 * bootstrapping or in a recently-started system.
+		 */
+		if (targetBlock == InvalidBlockNumber)
+		{
+			BlockNumber nblocks = RelationGetNumberOfBlocks(relation);
+
+			if (nblocks > 0)
+				targetBlock = nblocks - 1;
+		}
 	}
 
 loop:
@@ -479,14 +484,6 @@ loop:
 		{
 			/* use this page as future insert target, too */
 			RelationSetTargetBlock(relation, targetBlock);
-
-			/*
-			 * In case we used an in-memory map of available blocks, reset it
-			 * for next use.
-			 */
-			if (targetBlock < HEAP_FSM_CREATION_THRESHOLD)
-				FSMClearLocalMap();
-
 			return buffer;
 		}
 
@@ -546,12 +543,9 @@ loop:
 
 			/*
 			 * Check if some other backend has extended a block for us while
-			 * we were waiting on the lock.  We only check the FSM -- if there
-			 * isn't one we don't recheck the number of blocks.
+			 * we were waiting on the lock.
 			 */
-			targetBlock = GetPageWithFreeSpace(relation,
-											   len + saveFreeSpace,
-											   true);
+			targetBlock = GetPageWithFreeSpace(relation, len + saveFreeSpace);
 
 			/*
 			 * If some other waiter has already extended the relation, we
@@ -631,12 +625,5 @@ loop:
 	 */
 	RelationSetTargetBlock(relation, BufferGetBlockNumber(buffer));
 
-	/*
-	 * In case we used an in-memory map of available blocks, reset it for next
-	 * use.  We do this unconditionally since after relation extension we
-	 * can't skip this based on the targetBlock.
-	 */
-	FSMClearLocalMap();
-
 	return buffer;
 }

src/backend/access/heap/vacuumlazy.c

@@ -153,7 +153,7 @@ static BufferAccessStrategy vac_strategy;
 static void lazy_scan_heap(Relation onerel, int options,
 			   LVRelStats *vacrelstats, Relation *Irel, int nindexes,
 			   bool aggressive);
-static void lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats, BlockNumber nblocks);
+static void lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats);
 static bool lazy_check_needs_freeze(Buffer buf, bool *hastup);
 static void lazy_vacuum_index(Relation indrel,
 				  IndexBulkDeleteResult **stats,
@@ -758,7 +758,7 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
 			pgstat_progress_update_multi_param(2, hvp_index, hvp_val);
 
 			/* Remove tuples from heap */
-			lazy_vacuum_heap(onerel, vacrelstats, nblocks);
+			lazy_vacuum_heap(onerel, vacrelstats);
 
 			/*
 			 * Forget the now-vacuumed tuples, and press on, but be careful
@@ -896,7 +896,7 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
 			MarkBufferDirty(buf);
 			UnlockReleaseBuffer(buf);
 
-			RecordPageWithFreeSpace(onerel, blkno, freespace, nblocks);
+			RecordPageWithFreeSpace(onerel, blkno, freespace);
 			continue;
 		}
 
@@ -935,7 +935,7 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
 			}
 
 			UnlockReleaseBuffer(buf);
-			RecordPageWithFreeSpace(onerel, blkno, freespace, nblocks);
+			RecordPageWithFreeSpace(onerel, blkno, freespace);
 			continue;
 		}
 
@@ -1332,7 +1332,7 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
 		 * taken if there are no indexes.)
 		 */
 		if (vacrelstats->num_dead_tuples == prev_dead_count)
-			RecordPageWithFreeSpace(onerel, blkno, freespace, nblocks);
+			RecordPageWithFreeSpace(onerel, blkno, freespace);
 	}
 
 	/* report that everything is scanned and vacuumed */
@@ -1394,7 +1394,7 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
 		/* Remove tuples from heap */
 		pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
 									 PROGRESS_VACUUM_PHASE_VACUUM_HEAP);
-		lazy_vacuum_heap(onerel, vacrelstats, nblocks);
+		lazy_vacuum_heap(onerel, vacrelstats);
 		vacrelstats->num_index_scans++;
 	}
 
@@ -1465,10 +1465,9 @@ lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
  * Note: the reason for doing this as a second pass is we cannot remove
  * the tuples until we've removed their index entries, and we want to
  * process index entry removal in batches as large as possible.
- * Note: nblocks is passed as an optimization for RecordPageWithFreeSpace().
  */
 static void
-lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats, BlockNumber nblocks)
+lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats)
 {
 	int			tupindex;
 	int			npages;
@@ -1505,7 +1504,7 @@ lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats, BlockNumber nblocks)
 		freespace = PageGetHeapFreeSpace(page);
 
 		UnlockReleaseBuffer(buf);
-		RecordPageWithFreeSpace(onerel, tblk, freespace, nblocks);
+		RecordPageWithFreeSpace(onerel, tblk, freespace);
 		npages++;
 	}
 

src/backend/access/transam/xact.c

@@ -48,7 +48,6 @@
 #include "replication/walsender.h"
 #include "storage/condition_variable.h"
 #include "storage/fd.h"
-#include "storage/freespace.h"
 #include "storage/lmgr.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
@@ -2494,12 +2493,6 @@ AbortTransaction(void)
 	pgstat_report_wait_end();
 	pgstat_progress_end_command();
 
-	/*
-	 * In case we aborted during RelationGetBufferForTuple(), clear the local
-	 * map of heap pages.
-	 */
-	FSMClearLocalMap();
-
 	/* Clean up buffer I/O and buffer context locks, too */
 	AbortBufferIO();
 	UnlockBuffers();
@@ -4721,13 +4714,6 @@ AbortSubTransaction(void)
 
 	pgstat_report_wait_end();
 	pgstat_progress_end_command();
-
-	/*
-	 * In case we aborted during RelationGetBufferForTuple(), clear the local
-	 * map of heap pages.
-	 */
-	FSMClearLocalMap();
-
 	AbortBufferIO();
 	UnlockBuffers();