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Diffstat (limited to 'src/backend/access/nbtree/nbtree.c')
-rw-r--r--src/backend/access/nbtree/nbtree.c138
1 files changed, 103 insertions, 35 deletions
diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
index de6765415fe..c7f23da4c7a 100644
--- a/src/backend/access/nbtree/nbtree.c
+++ b/src/backend/access/nbtree/nbtree.c
@@ -12,7 +12,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.95 2003/02/21 00:06:21 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.96 2003/02/22 00:45:04 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -23,6 +23,7 @@
#include "access/nbtree.h"
#include "catalog/index.h"
#include "miscadmin.h"
+#include "storage/freespace.h"
/* Working state for btbuild and its callback */
@@ -44,7 +45,6 @@ typedef struct
} BTBuildState;
-bool BuildingBtree = false; /* see comment in btbuild() */
bool FastBuild = true; /* use SORT instead of insertion build */
/*
@@ -68,13 +68,7 @@ static void btbuildCallback(Relation index,
void
AtEOXact_nbtree(void)
{
- /*
- * Note: these actions should only be necessary during xact abort; but
- * they can't hurt during a commit.
- */
-
- /* If we were building a btree, we ain't anymore. */
- BuildingBtree = false;
+ /* nothing to do at the moment */
}
@@ -95,9 +89,6 @@ btbuild(PG_FUNCTION_ARGS)
double reltuples;
BTBuildState buildstate;
- /* set flag to disable locking */
- BuildingBtree = true;
-
/*
* bootstrap processing does something strange, so don't use
* sort/build for initial catalog indices. at some point i need to
@@ -172,9 +163,6 @@ btbuild(PG_FUNCTION_ARGS)
}
#endif /* BTREE_BUILD_STATS */
- /* all done */
- BuildingBtree = false;
-
/*
* Since we just counted the tuples in the heap, we update its stats
* in pg_class to guarantee that the planner takes advantage of the
@@ -689,10 +677,6 @@ btbulkdelete(PG_FUNCTION_ARGS)
* We now need to back up the scan one item, so that the next
* cycle will re-examine the same offnum on this page (which
* now holds the next item).
- *
- * For now, just hack the current-item index. Will need to
- * be smarter when deletion includes removal of empty
- * index pages.
*/
current->ip_posid--;
}
@@ -708,13 +692,90 @@ btbulkdelete(PG_FUNCTION_ARGS)
result = (IndexBulkDeleteResult *) palloc(sizeof(IndexBulkDeleteResult));
result->num_pages = num_pages;
- result->tuples_removed = tuples_removed;
result->num_index_tuples = num_index_tuples;
+ result->tuples_removed = tuples_removed;
+ result->pages_free = 0; /* not computed here */
PG_RETURN_POINTER(result);
}
/*
+ * Post-VACUUM cleanup.
+ *
+ * Here, we scan looking for pages we can delete or return to the freelist.
+ *
+ * Result: a palloc'd struct containing statistical info for VACUUM displays.
+ */
+Datum
+btvacuumcleanup(PG_FUNCTION_ARGS)
+{
+ Relation rel = (Relation) PG_GETARG_POINTER(0);
+#ifdef NOT_USED
+ IndexVacuumCleanupInfo *info = (IndexVacuumCleanupInfo *) PG_GETARG_POINTER(1);
+#endif
+ IndexBulkDeleteResult *stats = (IndexBulkDeleteResult *) PG_GETARG_POINTER(2);
+ BlockNumber num_pages;
+ BlockNumber blkno;
+ PageFreeSpaceInfo *pageSpaces;
+ int nFreePages,
+ maxFreePages;
+
+ Assert(stats != NULL);
+
+ num_pages = RelationGetNumberOfBlocks(rel);
+
+ /* No point in remembering more than MaxFSMPages pages */
+ maxFreePages = MaxFSMPages;
+ if ((BlockNumber) maxFreePages > num_pages)
+ maxFreePages = (int) num_pages + 1; /* +1 to avoid palloc(0) */
+ pageSpaces = (PageFreeSpaceInfo *) palloc(maxFreePages * sizeof(PageFreeSpaceInfo));
+ nFreePages = 0;
+
+ /*
+ * Scan through all pages of index, except metapage. (Any pages added
+ * after we start the scan will not be examined; this should be fine,
+ * since they can't possibly be empty.)
+ */
+ for (blkno = BTREE_METAPAGE+1; blkno < num_pages; blkno++)
+ {
+ Buffer buf;
+ Page page;
+ BTPageOpaque opaque;
+
+ buf = _bt_getbuf(rel, blkno, BT_READ);
+ page = BufferGetPage(buf);
+ opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+ if (P_ISDELETED(opaque))
+ {
+ /* XXX if safe-to-reclaim... */
+ if (nFreePages < maxFreePages)
+ {
+ pageSpaces[nFreePages].blkno = blkno;
+ /* The avail-space value is bogus, but must be < BLCKSZ */
+ pageSpaces[nFreePages].avail = BLCKSZ-1;
+ nFreePages++;
+ }
+ }
+ _bt_relbuf(rel, buf);
+ }
+
+ /*
+ * Update the shared Free Space Map with the info we now have about
+ * free space in the index, discarding any old info the map may have.
+ * We do not need to sort the page numbers; they're in order already.
+ */
+ MultiRecordFreeSpace(&rel->rd_node, 0, nFreePages, pageSpaces);
+
+ pfree(pageSpaces);
+
+ /* update statistics */
+ stats->num_pages = num_pages;
+ stats->pages_free = nFreePages;
+
+ PG_RETURN_POINTER(stats);
+}
+
+/*
* Restore scan position when btgettuple is called to continue a scan.
*
* This is nontrivial because concurrent insertions might have moved the
@@ -739,7 +800,7 @@ _bt_restscan(IndexScanDesc scan)
maxoff;
BTPageOpaque opaque;
Buffer nextbuf;
- ItemPointerData target = so->curHeapIptr;
+ ItemPointer target = &(so->curHeapIptr);
BTItem item;
BlockNumber blkno;
@@ -759,7 +820,7 @@ _bt_restscan(IndexScanDesc scan)
* current->ip_posid before first index tuple on the current page
* (_bt_step will move it right)... XXX still needed?
*/
- if (!ItemPointerIsValid(&target))
+ if (!ItemPointerIsValid(target))
{
ItemPointerSetOffsetNumber(current,
OffsetNumberPrev(P_FIRSTDATAKEY(opaque)));
@@ -778,11 +839,7 @@ _bt_restscan(IndexScanDesc scan)
offnum = OffsetNumberNext(offnum))
{
item = (BTItem) PageGetItem(page, PageGetItemId(page, offnum));
- if (item->bti_itup.t_tid.ip_blkid.bi_hi ==
- target.ip_blkid.bi_hi &&
- item->bti_itup.t_tid.ip_blkid.bi_lo ==
- target.ip_blkid.bi_lo &&
- item->bti_itup.t_tid.ip_posid == target.ip_posid)
+ if (BTTidSame(item->bti_itup.t_tid, *target))
{
/* Found it */
current->ip_posid = offnum;
@@ -793,22 +850,33 @@ _bt_restscan(IndexScanDesc scan)
/*
* The item we're looking for moved right at least one page, so
* move right. We are careful here to pin and read-lock the next
- * page before releasing the current one. This ensures that a
- * concurrent btbulkdelete scan cannot pass our position --- if it
+ * non-dead page before releasing the current one. This ensures that
+ * a concurrent btbulkdelete scan cannot pass our position --- if it
* did, it might be able to reach and delete our target item before
* we can find it again.
*/
if (P_RIGHTMOST(opaque))
- elog(FATAL, "_bt_restscan: my bits moved right off the end of the world!"
+ elog(ERROR, "_bt_restscan: my bits moved right off the end of the world!"
"\n\tRecreate index %s.", RelationGetRelationName(rel));
-
- blkno = opaque->btpo_next;
- nextbuf = _bt_getbuf(rel, blkno, BT_READ);
+ /* Advance to next non-dead page --- there must be one */
+ nextbuf = InvalidBuffer;
+ for (;;)
+ {
+ blkno = opaque->btpo_next;
+ if (nextbuf != InvalidBuffer)
+ _bt_relbuf(rel, nextbuf);
+ nextbuf = _bt_getbuf(rel, blkno, BT_READ);
+ page = BufferGetPage(nextbuf);
+ opaque = (BTPageOpaque) PageGetSpecialPointer(page);
+ if (!P_IGNORE(opaque))
+ break;
+ if (P_RIGHTMOST(opaque))
+ elog(ERROR, "_bt_restscan: fell off the end of %s",
+ RelationGetRelationName(rel));
+ }
_bt_relbuf(rel, buf);
so->btso_curbuf = buf = nextbuf;
- page = BufferGetPage(buf);
maxoff = PageGetMaxOffsetNumber(page);
- opaque = (BTPageOpaque) PageGetSpecialPointer(page);
offnum = P_FIRSTDATAKEY(opaque);
ItemPointerSet(current, blkno, offnum);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-23 05:34:15 +0000