1. Reap deleted/unused tuples on page-base
2. Reap unused tuples too 3. Reap empty pages 4. Check if a page is initialized, initialize it if not and reap it 5. Binary search in list of reapped pages/tids to check is the heap' tid pointed by a index' tuple on this list (it's mu-u-uch faster)
This commit is contained in:
Vadim B. Mikheev
parent
327d900b51
commit
bc50067426
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@ -7,7 +7,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.3 1996/10/03 20:11:41 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.4 1996/10/18 08:13:36 vadim Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -41,6 +41,13 @@
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#include "commands/vacuum.h"
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#ifdef NEED_RUSAGE
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#include "rusagestub.h"
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#else /* NEED_RUSAGE */
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#include <sys/time.h>
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#include <sys/resource.h>
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#endif /* NEED_RUSAGE */
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bool VacuumRunning = false;
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/* non-export function prototypes */
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@ -54,13 +61,15 @@ static void _vc_vacindices(VRelList curvrl, Relation onerel);
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static void _vc_vaconeind(VRelList curvrl, Relation indrel);
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static void _vc_updstats(Oid relid, int npages, int ntuples, bool hasindex);
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static void _vc_setpagelock(Relation rel, BlockNumber blkno);
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static bool _vc_ontidlist(ItemPointer itemptr, VTidList tidlist);
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static void _vc_reaptid(Portal p, VRelList curvrl, BlockNumber blkno,
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OffsetNumber offnum);
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static bool _vc_tidreapped(ItemPointer itemptr, VRelList curvrl, Relation indrel);
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static void _vc_reappage(Portal p, VRelList curvrl, VPageDescr vpc);
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static void _vc_free(Portal p, VRelList vrl);
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static Relation _vc_getarchrel(Relation heaprel);
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static void _vc_archive(Relation archrel, HeapTuple htup);
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static bool _vc_isarchrel(char *rname);
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static char * _vc_find_eq (char *bot, int nelem, int size, char *elm, int (*compar)(char *, char *));
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static int _vc_cmp_blk (char *left, char *right);
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static int _vc_cmp_offno (char *left, char *right);
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void
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vacuum(char *vacrel)
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@ -280,7 +289,8 @@ _vc_getrels(Portal p, NameData *VacRelP)
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cur->vrl_relid = pgctup->t_oid;
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cur->vrl_attlist = (VAttList) NULL;
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cur->vrl_tidlist = (VTidList) NULL;
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cur->vrl_pgdsc = (VPageDescr*) NULL;
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cur->vrl_nrepg = 0;
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cur->vrl_npages = cur->vrl_ntups = 0;
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cur->vrl_hasindex = false;
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cur->vrl_next = (VRelList) NULL;
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@ -355,7 +365,7 @@ _vc_vacone(Portal p, VRelList curvrl)
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_vc_vacheap(p, curvrl, onerel);
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/* if we vacuumed any heap tuples, vacuum the indices too */
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if (curvrl->vrl_tidlist != (VTidList) NULL)
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if (curvrl->vrl_nrepg > 0)
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_vc_vacindices(curvrl, onerel);
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else
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curvrl->vrl_hasindex = onerel->rd_rel->relhasindex;
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@ -372,6 +382,9 @@ _vc_vacone(Portal p, VRelList curvrl)
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CommitTransactionCommand();
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}
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# define ADJUST_FREE_SPACE(S)\
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((DOUBLEALIGN(S) == (S)) ? (S) : (DOUBLEALIGN(S) - sizeof(double)))
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/*
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* _vc_vacheap() -- vacuum an open heap relation
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*
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@ -398,24 +411,24 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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bool pgchanged, tupgone;
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AbsoluteTime purgetime, expiretime;
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RelativeTime preservetime;
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char *relname;
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VPageDescr vpc;
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uint32 nunused, nempg, nnepg, nchpg;
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Size frsize;
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struct rusage ru0, ru1;
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getrusage(RUSAGE_SELF, &ru0);
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relname = (RelationGetRelationName(onerel))->data;
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nvac = 0;
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ntups = 0;
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nunused = nempg = nnepg = nchpg = 0;
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frsize = 0;
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curvrl->vrl_nrepg = 0;
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nblocks = RelationGetNumberOfBlocks(onerel);
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{
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char *relname;
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relname = (RelationGetRelationName(onerel))->data;
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if ( (strlen(relname) > 4) &&
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relname[0] == 'X' &&
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relname[1] == 'i' &&
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relname[2] == 'n' &&
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(relname[3] == 'v' || relname[3] == 'x'))
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return;
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}
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/* if the relation has an archive, open it */
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if (onerel->rd_rel->relarch != 'n') {
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isarchived = true;
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@ -425,17 +438,12 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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/* don't vacuum large objects for now.
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something breaks when we do*/
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{
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char *relname;
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relname = (RelationGetRelationName(onerel))->data;
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if ( (strlen(relname) > 4) &&
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relname[0] == 'X' &&
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relname[1] == 'i' &&
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relname[2] == 'n' &&
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(relname[3] == 'v' || relname[3] == 'x'))
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if ( (strlen(relname) > 4) &&
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relname[0] == 'X' &&
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relname[1] == 'i' &&
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relname[2] == 'n' &&
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(relname[3] == 'v' || relname[3] == 'x'))
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return;
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}
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/* calculate the purge time: tuples that expired before this time
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will be archived or deleted */
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@ -452,12 +460,34 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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else if (AbsoluteTimeIsBackwardCompatiblyValid(expiretime))
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purgetime = expiretime;
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vpc = (VPageDescr) palloc (sizeof(VPageDescrData) + MaxOffsetNumber*sizeof(OffsetNumber));
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for (blkno = 0; blkno < nblocks; blkno++) {
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buf = ReadBuffer(onerel, blkno);
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page = BufferGetPage(buf);
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vpc->vpd_blkno = blkno;
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vpc->vpd_noff = 0;
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if (PageIsNew(page)) {
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elog (NOTICE, "Rel %.*s: Uninitialized page %u - fixing",
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NAMEDATALEN, relname, blkno);
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PageInit (page, BufferGetPageSize (buf), 0);
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vpc->vpd_free = PageGetFreeSpace (page);
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vpc->vpd_free = ADJUST_FREE_SPACE (vpc->vpd_free);
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frsize += vpc->vpd_free;
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nnepg++;
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_vc_reappage(p, curvrl, vpc); /* No one index should point here */
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WriteBuffer(buf);
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continue;
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}
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if (PageIsEmpty(page)) {
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vpc->vpd_free = PageGetFreeSpace (page);
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vpc->vpd_free = ADJUST_FREE_SPACE (vpc->vpd_free);
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frsize += vpc->vpd_free;
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nempg++;
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_vc_reappage(p, curvrl, vpc); /* No one index should point here */
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ReleaseBuffer(buf);
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continue;
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}
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@ -469,8 +499,11 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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offnum = OffsetNumberNext(offnum)) {
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itemid = PageGetItemId(page, offnum);
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if (!ItemIdIsUsed(itemid))
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if (!ItemIdIsUsed(itemid)) {
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vpc->vpd_voff[vpc->vpd_noff++] = offnum;
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nunused++;
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continue;
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}
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htup = (HeapTuple) PageGetItem(page, itemid);
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tupgone = false;
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@ -479,7 +512,6 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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TransactionIdIsValid((TransactionId)htup->t_xmin)) {
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if (TransactionIdDidAbort(htup->t_xmin)) {
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_vc_reaptid(p, curvrl, blkno, offnum);
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pgchanged = true;
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tupgone = true;
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} else if (TransactionIdDidCommit(htup->t_xmin)) {
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@ -504,8 +536,7 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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* before purgetime.
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*/
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if (!tupgone && htup->t_tmax < purgetime) {
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_vc_reaptid(p, curvrl, blkno, offnum);
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if (htup->t_tmax < purgetime) {
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tupgone = true;
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pgchanged = true;
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}
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@ -522,6 +553,8 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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/* mark it unused */
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lpp->lp_flags &= ~LP_USED;
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vpc->vpd_voff[vpc->vpd_noff++] = offnum;
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++nvac;
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} else {
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ntups++;
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@ -530,8 +563,21 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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if (pgchanged) {
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PageRepairFragmentation(page);
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if ( vpc->vpd_noff > 0 ) { /* there are some new unused tids here */
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vpc->vpd_free = PageGetFreeSpace (page);
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vpc->vpd_free = ADJUST_FREE_SPACE (vpc->vpd_free);
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frsize += vpc->vpd_free;
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_vc_reappage(p, curvrl, vpc);
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}
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WriteBuffer(buf);
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nchpg++;
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} else {
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if ( vpc->vpd_noff > 0 ) { /* there are only old unused tids here */
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vpc->vpd_free = PageGetFreeSpace (page);
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vpc->vpd_free = ADJUST_FREE_SPACE (vpc->vpd_free);
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frsize += vpc->vpd_free;
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_vc_reappage(p, curvrl, vpc);
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}
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ReleaseBuffer(buf);
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}
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}
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@ -542,6 +588,18 @@ _vc_vacheap(Portal p, VRelList curvrl, Relation onerel)
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/* save stats in the rel list for use later */
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curvrl->vrl_ntups = ntups;
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curvrl->vrl_npages = nblocks;
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getrusage(RUSAGE_SELF, &ru1);
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elog (NOTICE, "Rel %.*s: Pages %u: Changed %u, Reapped %u, Empty %u, New %u; \
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Tuples %u: Vac %u, UnUsed %u; FreeSpace %u. Elapsed %u/%u sec.",
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NAMEDATALEN, relname,
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nblocks, nchpg, curvrl->vrl_nrepg, nempg, nnepg,
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ntups, nvac, nunused, frsize,
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ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
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ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
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pfree (vpc);
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}
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/*
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@ -613,11 +671,10 @@ _vc_vacindices(VRelList curvrl, Relation onerel)
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* _vc_vaconeind() -- vacuum one index relation.
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*
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* Curvrl is the VRelList entry for the heap we're currently vacuuming.
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* It's locked. The vrl_tidlist entry in curvrl is the list of deleted
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* heap tids, sorted in reverse (page, offset) order. Onerel is an
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* index relation on the vacuumed heap. We don't set locks on the index
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* relation here, since the indexed access methods support locking at
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* different granularities. We let them handle it.
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* It's locked. Onerel is an index relation on the vacuumed heap.
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* We don't set locks on the index relation here, since the indexed
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* access methods support locking at different granularities.
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* We let them handle it.
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*
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* Finally, we arrange to update the index relation's statistics in
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* pg_class.
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@ -631,6 +688,9 @@ _vc_vaconeind(VRelList curvrl, Relation indrel)
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int nvac;
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int nitups;
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int nipages;
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struct rusage ru0, ru1;
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getrusage(RUSAGE_SELF, &ru0);
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/* walk through the entire index */
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iscan = index_beginscan(indrel, false, 0, (ScanKey) NULL);
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@ -641,7 +701,7 @@ _vc_vaconeind(VRelList curvrl, Relation indrel)
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!= (RetrieveIndexResult) NULL) {
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heapptr = &res->heap_iptr;
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if (_vc_ontidlist(heapptr, curvrl->vrl_tidlist)) {
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if (_vc_tidreapped(heapptr, curvrl, indrel)) {
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#if 0
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elog(DEBUG, "<%x,%x> -> <%x,%x>",
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ItemPointerGetBlockNumber(&(res->index_iptr)),
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@ -664,6 +724,14 @@ _vc_vaconeind(VRelList curvrl, Relation indrel)
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/* now update statistics in pg_class */
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nipages = RelationGetNumberOfBlocks(indrel);
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_vc_updstats(indrel->rd_id, nipages, nitups, false);
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getrusage(RUSAGE_SELF, &ru1);
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elog (NOTICE, "Ind %.*s: Pages %u; Tuples %u: Deleted %u. Elapsed %u/%u sec.",
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NAMEDATALEN, indrel->rd_rel->relname.data, nipages, nitups, nvac,
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ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
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ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
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}
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/*
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@ -727,74 +795,87 @@ static void _vc_setpagelock(Relation rel, BlockNumber blkno)
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}
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/*
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* _vc_ontidlist() -- is a particular tid on the supplied tid list?
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* _vc_tidreapped() -- is a particular tid reapped?
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*
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* Tidlist is sorted in reverse (page, offset) order.
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* VPageDescr array is sorted in right order.
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*/
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static bool
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_vc_ontidlist(ItemPointer itemptr, VTidList tidlist)
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_vc_tidreapped(ItemPointer itemptr, VRelList curvrl, Relation indrel)
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{
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BlockNumber ibkno;
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OffsetNumber ioffno;
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ItemPointer check;
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BlockNumber ckbkno;
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OffsetNumber ckoffno;
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OffsetNumber *voff;
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VPageDescr vp, *vpp;
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VPageDescrData vpd;
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ibkno = ItemPointerGetBlockNumber(itemptr);
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vpd.vpd_blkno = ItemPointerGetBlockNumber(itemptr);
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ioffno = ItemPointerGetOffsetNumber(itemptr);
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vp = &vpd;
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vpp = (VPageDescr*) _vc_find_eq ((char*)(curvrl->vrl_pgdsc),
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curvrl->vrl_nrepg, sizeof (VPageDescr), (char*)&vp,
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_vc_cmp_blk);
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while (tidlist != (VTidList) NULL) {
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check = &(tidlist->vtl_tid);
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ckbkno = ItemPointerGetBlockNumber(check);
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ckoffno = ItemPointerGetOffsetNumber(check);
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if ( vpp == (VPageDescr*) NULL )
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return (false);
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vp = *vpp;
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/* see if we've looked far enough down the list */
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if ((ckbkno < ibkno) || (ckbkno == ibkno && ckoffno < ioffno))
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return (false);
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/* ok - we are on true page */
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/* see if we have a match */
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if (ckbkno == ibkno && ckoffno == ioffno)
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return (true);
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/* check next */
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tidlist = tidlist->vtl_next;
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if ( vp->vpd_noff == 0 ) { /* this is EmptyPage !!! */
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elog (NOTICE, "Ind %.*s: pointer to EmptyPage (blk %u off %u) - fixing",
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NAMEDATALEN, indrel->rd_rel->relname.data,
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vpd.vpd_blkno, ioffno);
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return (true);
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}
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voff = (OffsetNumber*) _vc_find_eq ((char*)(vp->vpd_voff),
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vp->vpd_noff, sizeof (OffsetNumber), (char*)&ioffno,
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_vc_cmp_offno);
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if ( voff == (OffsetNumber*) NULL )
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return (false);
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return (true);
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} /* _vc_tidreapped */
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/* ran off the end of the list without finding a match */
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return (false);
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}
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/*
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* _vc_reaptid() -- save a tid on the list of reaped tids for the current
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* _vc_reappage() -- save a page on the array of reaped pages for the current
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* entry on the vacuum relation list.
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*
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* As a side effect of the way that the vacuuming loop for a given
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* relation works, the tids of vacuumed tuples wind up in reverse
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* order in the list -- highest tid on a page is first, and higher
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* pages come before lower pages. This is important later when we
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* vacuum the indices, as it gives us a way of stopping the search
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* for a tid if we notice we've passed the page it would be on.
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* relation works, higher pages come after lower pages in the array
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* (and highest tid on a page is last).
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*/
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static void
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_vc_reaptid(Portal p,
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_vc_reappage(Portal p,
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VRelList curvrl,
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BlockNumber blkno,
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OffsetNumber offnum)
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VPageDescr vpc)
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{
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PortalVariableMemory pmem;
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MemoryContext old;
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VTidList newvtl;
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VPageDescr newvpd;
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/* allocate a VTidListData entry in the portal memory context */
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/* allocate a VPageDescrData entry in the portal memory context */
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pmem = PortalGetVariableMemory(p);
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old = MemoryContextSwitchTo((MemoryContext) pmem);
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newvtl = (VTidList) palloc(sizeof(VTidListData));
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if ( curvrl->vrl_nrepg == 0 )
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curvrl->vrl_pgdsc = (VPageDescr*) palloc(100*sizeof(VPageDescr));
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else if ( curvrl->vrl_nrepg % 100 == 0 )
|
||||
curvrl->vrl_pgdsc = (VPageDescr*) repalloc(curvrl->vrl_pgdsc, (curvrl->vrl_nrepg+100)*sizeof(VPageDescr));
|
||||
newvpd = (VPageDescr) palloc(sizeof(VPageDescrData) + vpc->vpd_noff*sizeof(OffsetNumber));
|
||||
MemoryContextSwitchTo(old);
|
||||
|
||||
/* fill it in */
|
||||
ItemPointerSet(&(newvtl->vtl_tid), blkno, offnum);
|
||||
newvtl->vtl_next = curvrl->vrl_tidlist;
|
||||
curvrl->vrl_tidlist = newvtl;
|
||||
if ( vpc->vpd_noff > 0 )
|
||||
memmove (newvpd->vpd_voff, vpc->vpd_voff, vpc->vpd_noff*sizeof(OffsetNumber));
|
||||
newvpd->vpd_blkno = vpc->vpd_blkno;
|
||||
newvpd->vpd_free = vpc->vpd_free;
|
||||
newvpd->vpd_noff = vpc->vpd_noff;
|
||||
|
||||
curvrl->vrl_pgdsc[curvrl->vrl_nrepg] = newvpd;
|
||||
(curvrl->vrl_nrepg)++;
|
||||
}
|
||||
|
||||
static void
|
||||
|
|
@ -802,7 +883,8 @@ _vc_free(Portal p, VRelList vrl)
|
|||
{
|
||||
VRelList p_vrl;
|
||||
VAttList p_val, val;
|
||||
VTidList p_vtl, vtl;
|
||||
VPageDescr p_vpd, *vpd;
|
||||
int i;
|
||||
MemoryContext old;
|
||||
PortalVariableMemory pmem;
|
||||
|
||||
|
|
@ -819,12 +901,13 @@ _vc_free(Portal p, VRelList vrl)
|
|||
pfree(p_val);
|
||||
}
|
||||
|
||||
/* free tid list */
|
||||
vtl = vrl->vrl_tidlist;
|
||||
while (vtl != (VTidList) NULL) {
|
||||
p_vtl = vtl;
|
||||
vtl = vtl->vtl_next;
|
||||
pfree(p_vtl);
|
||||
/* free page' descriptions */
|
||||
if ( vrl->vrl_nrepg > 0 ) {
|
||||
vpd = vrl->vrl_pgdsc;
|
||||
for (i = 0; i < vrl->vrl_nrepg; i++) {
|
||||
pfree(vpd[i]);
|
||||
}
|
||||
pfree (vpd);
|
||||
}
|
||||
|
||||
/* free rel list entry */
|
||||
|
|
@ -880,3 +963,84 @@ _vc_isarchrel(char *rname)
|
|||
|
||||
return (false);
|
||||
}
|
||||
|
||||
static char *
|
||||
_vc_find_eq (char *bot, int nelem, int size, char *elm, int (*compar)(char *, char *))
|
||||
{
|
||||
int res;
|
||||
int last = nelem - 1;
|
||||
int celm = nelem / 2;
|
||||
bool last_move, first_move;
|
||||
|
||||
last_move = first_move = true;
|
||||
for ( ; ; )
|
||||
{
|
||||
if ( first_move == true )
|
||||
{
|
||||
res = compar (bot, elm);
|
||||
if ( res > 0 )
|
||||
return (NULL);
|
||||
if ( res == 0 )
|
||||
return (bot);
|
||||
first_move = false;
|
||||
}
|
||||
if ( last_move == true )
|
||||
{
|
||||
res = compar (elm, bot + last*size);
|
||||
if ( res > 0 )
|
||||
return (NULL);
|
||||
if ( res == 0 )
|
||||
return (bot + last*size);
|
||||
last_move = false;
|
||||
}
|
||||
res = compar (elm, bot + celm*size);
|
||||
if ( res == 0 )
|
||||
return (bot + celm*size);
|
||||
if ( res < 0 )
|
||||
{
|
||||
if ( celm == 0 )
|
||||
return (NULL);
|
||||
last = celm - 1;
|
||||
celm = celm / 2;
|
||||
last_move = true;
|
||||
continue;
|
||||
}
|
||||
|
||||
if ( celm == last )
|
||||
return (NULL);
|
||||
|
||||
last = last - celm - 1;
|
||||
bot = bot + (celm+1)*size;
|
||||
celm = (last + 1) / 2;
|
||||
first_move = true;
|
||||
}
|
||||
|
||||
} /* _vc_find_eq */
|
||||
|
||||
static int
|
||||
_vc_cmp_blk (char *left, char *right)
|
||||
{
|
||||
BlockNumber lblk, rblk;
|
||||
|
||||
lblk = (*((VPageDescr*)left))->vpd_blkno;
|
||||
rblk = (*((VPageDescr*)right))->vpd_blkno;
|
||||
|
||||
if ( lblk < rblk )
|
||||
return (-1);
|
||||
if ( lblk == rblk )
|
||||
return (0);
|
||||
return (1);
|
||||
|
||||
} /* _vc_cmp_blk */
|
||||
|
||||
static int
|
||||
_vc_cmp_offno (char *left, char *right)
|
||||
{
|
||||
|
||||
if ( *(OffsetNumber*)left < *(OffsetNumber*)right )
|
||||
return (-1);
|
||||
if ( *(OffsetNumber*)left == *(OffsetNumber*)right )
|
||||
return (0);
|
||||
return (1);
|
||||
|
||||
} /* _vc_cmp_offno */
|
||||
|
|
|
|||
Loading…
Reference in New Issue