Move index vacuum routines to vacuum.c.

An upcoming patch moves parallel vacuum code out of vacuumlazy.c. This
code restructuring will allow both lazy vacuum and parallel vacuum to use
index vacuum functions.

Author: Masahiko Sawada
Reviewed-by: Hou Zhijie, Amit Kapila
Discussion: https://www.postgresql.org/message-id/20211030212101.ae3qcouatwmy7tbr%40alap3.anarazel.de

Author: Amit Kapila

src/backend/access/heap/vacuumlazy.c

@@ -149,26 +149,6 @@ typedef enum
 	VACUUM_ERRCB_PHASE_TRUNCATE
 } VacErrPhase;
 
-/*
- * LVDeadItems stores TIDs whose index tuples are deleted by index vacuuming.
- * Each TID points to an LP_DEAD line pointer from a heap page that has been
- * processed by lazy_scan_prune.
- *
- * Also needed by lazy_vacuum_heap_rel, which marks the same LP_DEAD line
- * pointers as LP_UNUSED during second heap pass.
- */
-typedef struct LVDeadItems
-{
-	int			max_items;		/* # slots allocated in array */
-	int			num_items;		/* current # of entries */
-
-	/* Sorted array of TIDs to delete from indexes */
-	ItemPointerData items[FLEXIBLE_ARRAY_MEMBER];
-} LVDeadItems;
-
-#define MAXDEADITEMS(avail_mem) \
-	(((avail_mem) - offsetof(LVDeadItems, items)) / sizeof(ItemPointerData))
-
 /*
  * Shared information among parallel workers.  So this is allocated in the DSM
  * segment.
@@ -339,9 +319,15 @@ typedef struct LVRelState
 	VacErrPhase phase;
 
 	/*
-	 * State managed by lazy_scan_heap() follows
+	 * State managed by lazy_scan_heap() follows.
+	 *
+	 * dead_items stores TIDs whose index tuples are deleted by index
+	 * vacuuming. Each TID points to an LP_DEAD line pointer from a heap page
+	 * that has been processed by lazy_scan_prune.  Also needed by
+	 * lazy_vacuum_heap_rel, which marks the same LP_DEAD line pointers as
+	 * LP_UNUSED during second heap pass.
 	 */
-	LVDeadItems *dead_items;	/* TIDs whose index tuples we'll delete */
+	VacDeadItems *dead_items;	/* TIDs whose index tuples we'll delete */
 	BlockNumber rel_pages;		/* total number of pages */
 	BlockNumber scanned_pages;	/* number of pages we examined */
 	BlockNumber pinskipped_pages;	/* # of pages skipped due to a pin */
@@ -434,11 +420,8 @@ static void lazy_truncate_heap(LVRelState *vacrel);
 static BlockNumber count_nondeletable_pages(LVRelState *vacrel,
 											bool *lock_waiter_detected);
 static int dead_items_max_items(LVRelState *vacrel);
-static inline Size max_items_to_alloc_size(int max_items);
 static void dead_items_alloc(LVRelState *vacrel, int nworkers);
 static void dead_items_cleanup(LVRelState *vacrel);
-static bool lazy_tid_reaped(ItemPointer itemptr, void *state);
-static int	vac_cmp_itemptr(const void *left, const void *right);
 static bool heap_page_is_all_visible(LVRelState *vacrel, Buffer buf,
 									 TransactionId *visibility_cutoff_xid, bool *all_frozen);
 static int	parallel_vacuum_compute_workers(LVRelState *vacrel, int nrequested,
@@ -905,7 +888,7 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 static void
 lazy_scan_heap(LVRelState *vacrel, VacuumParams *params, bool aggressive)
 {
-	LVDeadItems *dead_items;
+	VacDeadItems *dead_items;
 	BlockNumber nblocks,
 				blkno,
 				next_unskippable_block,
@@ -2040,7 +2023,7 @@ lazy_scan_prune(LVRelState *vacrel,
 	 */
 	if (lpdead_items > 0)
 	{
-		LVDeadItems *dead_items = vacrel->dead_items;
+		VacDeadItems *dead_items = vacrel->dead_items;
 		ItemPointerData tmp;
 
 		Assert(!prunestate->all_visible);
@@ -2404,7 +2387,7 @@ static int
 lazy_vacuum_heap_page(LVRelState *vacrel, BlockNumber blkno, Buffer buffer,
 					  int index, Buffer *vmbuffer)
 {
-	LVDeadItems *dead_items = vacrel->dead_items;
+	VacDeadItems *dead_items = vacrel->dead_items;
 	Page		page = BufferGetPage(buffer);
 	OffsetNumber unused[MaxHeapTuplesPerPage];
 	int			uncnt = 0;
@@ -3019,11 +3002,8 @@ lazy_vacuum_one_index(Relation indrel, IndexBulkDeleteResult *istat,
 					  double reltuples, LVRelState *vacrel)
 {
 	IndexVacuumInfo ivinfo;
-	PGRUsage	ru0;
 	LVSavedErrInfo saved_err_info;
 
-	pg_rusage_init(&ru0);
-
 	ivinfo.index = indrel;
 	ivinfo.analyze_only = false;
 	ivinfo.report_progress = false;
@@ -3045,13 +3025,7 @@ lazy_vacuum_one_index(Relation indrel, IndexBulkDeleteResult *istat,
 							 InvalidBlockNumber, InvalidOffsetNumber);
 
 	/* Do bulk deletion */
-	istat = index_bulk_delete(&ivinfo, istat, lazy_tid_reaped,
-							  (void *) vacrel->dead_items);
-
-	ereport(elevel,
-			(errmsg("scanned index \"%s\" to remove %d row versions",
-					vacrel->indname, vacrel->dead_items->num_items),
-			 errdetail_internal("%s", pg_rusage_show(&ru0))));
+	istat = vac_bulkdel_one_index(&ivinfo, istat, (void *) vacrel->dead_items);
 
 	/* Revert to the previous phase information for error traceback */
 	restore_vacuum_error_info(vacrel, &saved_err_info);
@@ -3076,11 +3050,8 @@ lazy_cleanup_one_index(Relation indrel, IndexBulkDeleteResult *istat,
 					   LVRelState *vacrel)
 {
 	IndexVacuumInfo ivinfo;
-	PGRUsage	ru0;
 	LVSavedErrInfo saved_err_info;
 
-	pg_rusage_init(&ru0);
-
 	ivinfo.index = indrel;
 	ivinfo.analyze_only = false;
 	ivinfo.report_progress = false;
@@ -3102,24 +3073,7 @@ lazy_cleanup_one_index(Relation indrel, IndexBulkDeleteResult *istat,
 							 VACUUM_ERRCB_PHASE_INDEX_CLEANUP,
 							 InvalidBlockNumber, InvalidOffsetNumber);
 
-	istat = index_vacuum_cleanup(&ivinfo, istat);
-
-	if (istat)
-	{
-		ereport(elevel,
-				(errmsg("index \"%s\" now contains %.0f row versions in %u pages",
-						RelationGetRelationName(indrel),
-						istat->num_index_tuples,
-						istat->num_pages),
-				 errdetail("%.0f index row versions were removed.\n"
-						   "%u index pages were newly deleted.\n"
-						   "%u index pages are currently deleted, of which %u are currently reusable.\n"
-						   "%s.",
-						   istat->tuples_removed,
-						   istat->pages_newly_deleted,
-						   istat->pages_deleted, istat->pages_free,
-						   pg_rusage_show(&ru0))));
-	}
+	istat = vac_cleanup_one_index(&ivinfo, istat);
 
 	/* Revert to the previous phase information for error traceback */
 	restore_vacuum_error_info(vacrel, &saved_err_info);
@@ -3481,19 +3435,6 @@ dead_items_max_items(LVRelState *vacrel)
 	return (int) max_items;
 }
 
-/*
- * Returns the total required space for VACUUM's dead_items array given a
- * max_items value returned by dead_items_max_items
- */
-static inline Size
-max_items_to_alloc_size(int max_items)
-{
-	Assert(max_items >= MaxHeapTuplesPerPage);
-	Assert(max_items <= MAXDEADITEMS(MaxAllocSize));
-
-	return offsetof(LVDeadItems, items) + sizeof(ItemPointerData) * max_items;
-}
-
 /*
  * Allocate dead_items (either using palloc, or in dynamic shared memory).
  * Sets dead_items in vacrel for caller.
@@ -3504,7 +3445,7 @@ max_items_to_alloc_size(int max_items)
 static void
 dead_items_alloc(LVRelState *vacrel, int nworkers)
 {
-	LVDeadItems *dead_items;
+	VacDeadItems *dead_items;
 	int			max_items;
 
 	/*
@@ -3539,7 +3480,7 @@ dead_items_alloc(LVRelState *vacrel, int nworkers)
 
 	/* Serial VACUUM case */
 	max_items = dead_items_max_items(vacrel);
-	dead_items = (LVDeadItems *) palloc(max_items_to_alloc_size(max_items));
+	dead_items = (VacDeadItems *) palloc(vac_max_items_to_alloc_size(max_items));
 	dead_items->max_items = max_items;
 	dead_items->num_items = 0;
 
@@ -3565,74 +3506,6 @@ dead_items_cleanup(LVRelState *vacrel)
 	parallel_vacuum_end(vacrel);
 }
 
-/*
- *	lazy_tid_reaped() -- is a particular tid deletable?
- *
- *		This has the right signature to be an IndexBulkDeleteCallback.
- *
- *		Assumes dead_items array is sorted (in ascending TID order).
- */
-static bool
-lazy_tid_reaped(ItemPointer itemptr, void *state)
-{
-	LVDeadItems *dead_items = (LVDeadItems *) state;
-	int64		litem,
-				ritem,
-				item;
-	ItemPointer res;
-
-	litem = itemptr_encode(&dead_items->items[0]);
-	ritem = itemptr_encode(&dead_items->items[dead_items->num_items - 1]);
-	item = itemptr_encode(itemptr);
-
-	/*
-	 * Doing a simple bound check before bsearch() is useful to avoid the
-	 * extra cost of bsearch(), especially if dead items on the heap are
-	 * concentrated in a certain range.  Since this function is called for
-	 * every index tuple, it pays to be really fast.
-	 */
-	if (item < litem || item > ritem)
-		return false;
-
-	res = (ItemPointer) bsearch((void *) itemptr,
-								(void *) dead_items->items,
-								dead_items->num_items,
-								sizeof(ItemPointerData),
-								vac_cmp_itemptr);
-
-	return (res != NULL);
-}
-
-/*
- * Comparator routines for use with qsort() and bsearch().
- */
-static int
-vac_cmp_itemptr(const void *left, const void *right)
-{
-	BlockNumber lblk,
-				rblk;
-	OffsetNumber loff,
-				roff;
-
-	lblk = ItemPointerGetBlockNumber((ItemPointer) left);
-	rblk = ItemPointerGetBlockNumber((ItemPointer) right);
-
-	if (lblk < rblk)
-		return -1;
-	if (lblk > rblk)
-		return 1;
-
-	loff = ItemPointerGetOffsetNumber((ItemPointer) left);
-	roff = ItemPointerGetOffsetNumber((ItemPointer) right);
-
-	if (loff < roff)
-		return -1;
-	if (loff > roff)
-		return 1;
-
-	return 0;
-}
-
 /*
  * Check if every tuple in the given page is visible to all current and future
  * transactions. Also return the visibility_cutoff_xid which is the highest
@@ -3873,7 +3746,7 @@ parallel_vacuum_begin(LVRelState *vacrel, int nrequested)
 	int			nindexes = vacrel->nindexes;
 	ParallelContext *pcxt;
 	LVShared   *shared;
-	LVDeadItems *dead_items;
+	VacDeadItems *dead_items;
 	LVParallelIndStats *pindstats;
 	BufferUsage *buffer_usage;
 	WalUsage   *wal_usage;
@@ -3927,7 +3800,7 @@ parallel_vacuum_begin(LVRelState *vacrel, int nrequested)
 
 	/* Estimate size for dead_items -- PARALLEL_VACUUM_KEY_DEAD_ITEMS */
 	max_items = dead_items_max_items(vacrel);
-	est_dead_items_len = max_items_to_alloc_size(max_items);
+	est_dead_items_len = vac_max_items_to_alloc_size(max_items);
 	shm_toc_estimate_chunk(&pcxt->estimator, est_dead_items_len);
 	shm_toc_estimate_keys(&pcxt->estimator, 1);
 
@@ -4011,8 +3884,8 @@ parallel_vacuum_begin(LVRelState *vacrel, int nrequested)
 	lps->lvshared = shared;
 
 	/* Prepare the dead_items space */
-	dead_items = (LVDeadItems *) shm_toc_allocate(pcxt->toc,
-												  est_dead_items_len);
+	dead_items = (VacDeadItems *) shm_toc_allocate(pcxt->toc,
+												   est_dead_items_len);
 	dead_items->max_items = max_items;
 	dead_items->num_items = 0;
 	MemSet(dead_items->items, 0, sizeof(ItemPointerData) * max_items);
@@ -4138,7 +4011,7 @@ parallel_vacuum_main(dsm_segment *seg, shm_toc *toc)
 	Relation   *indrels;
 	LVParallelIndStats *lvpindstats;
 	LVShared   *lvshared;
-	LVDeadItems *dead_items;
+	VacDeadItems *dead_items;
 	BufferUsage *buffer_usage;
 	WalUsage   *wal_usage;
 	int			nindexes;
@@ -4183,9 +4056,9 @@ parallel_vacuum_main(dsm_segment *seg, shm_toc *toc)
 														false);
 
 	/* Set dead_items space (set as worker's vacrel dead_items below) */
-	dead_items = (LVDeadItems *) shm_toc_lookup(toc,
-												PARALLEL_VACUUM_KEY_DEAD_ITEMS,
-												false);
+	dead_items = (VacDeadItems *) shm_toc_lookup(toc,
+												 PARALLEL_VACUUM_KEY_DEAD_ITEMS,
+												 false);
 
 	/* Set cost-based vacuum delay */
 	VacuumCostActive = (VacuumCostDelay > 0);