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postgres/src/backend/commands/vacuum.c
Bruce Momjian d8dbbc8cf9 vacuum fix.
1998-08-28 04:57:21 +00:00

2260 lines
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/*-------------------------------------------------------------------------
*
* vacuum.c--
* the postgres vacuum cleaner
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.78 1998/08/28 04:57:21 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include <sys/types.h>
#include <sys/file.h>
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "postgres.h"
#include "miscadmin.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/transam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/catname.h"
#include "catalog/index.h"
#include "catalog/pg_class.h"
#include "catalog/pg_index.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_statistic.h"
#include "catalog/pg_type.h"
#include "commands/vacuum.h"
#include "fmgr.h"
#include "parser/parse_oper.h"
#include "storage/bufmgr.h"
#include "storage/bufpage.h"
#include "storage/shmem.h"
#include "storage/smgr.h"
#include "storage/itemptr.h"
#include "storage/lmgr.h"
#include "utils/builtins.h"
#include "utils/inval.h"
#include "utils/mcxt.h"
#include "utils/portal.h"
#include "utils/syscache.h"
#ifndef HAVE_GETRUSAGE
#include <rusagestub.h>
#else
#include <sys/time.h>
#include <sys/resource.h>
#endif
/* #include <port-protos.h> *//* Why? */
extern int BlowawayRelationBuffers(Relation rel, BlockNumber block);
bool VacuumRunning = false;
static Portal vc_portal;
static int MESSAGE_LEVEL; /* message level */
#define swapLong(a,b) {long tmp; tmp=a; a=b; b=tmp;}
#define swapInt(a,b) {int tmp; tmp=a; a=b; b=tmp;}
#define swapDatum(a,b) {Datum tmp; tmp=a; a=b; b=tmp;}
#define VacAttrStatsEqValid(stats) ( stats->f_cmpeq.fn_addr != NULL )
#define VacAttrStatsLtGtValid(stats) ( stats->f_cmplt.fn_addr != NULL && \
stats->f_cmpgt.fn_addr != NULL && \
RegProcedureIsValid(stats->outfunc) )
/* non-export function prototypes */
static void vc_init(void);
static void vc_shutdown(void);
static void vc_vacuum(NameData *VacRelP, bool analyze, List *va_cols);
static VRelList vc_getrels(NameData *VacRelP);
static void vc_vacone(Oid relid, bool analyze, List *va_cols);
static void vc_scanheap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages);
static void vc_rpfheap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages, int nindices, Relation *Irel);
static void vc_vacheap(VRelStats *vacrelstats, Relation onerel, VPageList vpl);
static void vc_vacpage(Page page, VPageDescr vpd);
static void vc_vaconeind(VPageList vpl, Relation indrel, int num_tuples);
static void vc_scanoneind(Relation indrel, int num_tuples);
static void vc_attrstats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple);
static void vc_bucketcpy(AttributeTupleForm attr, Datum value, Datum *bucket, int16 *bucket_len);
static void vc_updstats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats);
static void vc_delhilowstats(Oid relid, int attcnt, int *attnums);
static void vc_setpagelock(Relation rel, BlockNumber blkno);
static VPageDescr vc_tidreapped(ItemPointer itemptr, VPageList vpl);
static void vc_reappage(VPageList vpl, VPageDescr vpc);
static void vc_vpinsert(VPageList vpl, VPageDescr vpnew);
static void vc_free(VRelList vrl);
static void vc_getindices(Oid relid, int *nindices, Relation **Irel);
static void vc_clsindices(int nindices, Relation *Irel);
static void vc_mkindesc(Relation onerel, int nindices, Relation *Irel, IndDesc **Idesc);
static char *vc_find_eq(char *bot, int nelem, int size, char *elm, int (*compar) (char *, char *));
static int vc_cmp_blk(char *left, char *right);
static int vc_cmp_offno(char *left, char *right);
static bool vc_enough_space(VPageDescr vpd, Size len);
void
vacuum(char *vacrel, bool verbose, bool analyze, List *va_spec)
{
char *pname;
MemoryContext old;
PortalVariableMemory pmem;
NameData VacRel;
List *le;
List *va_cols = NIL;
/*
* Create a portal for safe memory across transctions. We need to
* palloc the name space for it because our hash function expects the
* name to be on a longword boundary. CreatePortal copies the name to
* safe storage for us.
*/
pname = (char *) palloc(strlen(VACPNAME) + 1);
strcpy(pname, VACPNAME);
vc_portal = CreatePortal(pname);
pfree(pname);
if (verbose)
MESSAGE_LEVEL = NOTICE;
else
MESSAGE_LEVEL = DEBUG;
/* vacrel gets de-allocated on transaction commit */
if (vacrel)
strcpy(VacRel.data, vacrel);
pmem = PortalGetVariableMemory(vc_portal);
old = MemoryContextSwitchTo((MemoryContext) pmem);
if (va_spec != NIL && !analyze)
elog(ERROR, "Can't vacuum columns, only tables. You can 'vacuum analyze' columns.");
foreach(le, va_spec)
{
char *col = (char *) lfirst(le);
char *dest;
dest = (char *) palloc(strlen(col) + 1);
strcpy(dest, col);
va_cols = lappend(va_cols, dest);
}
MemoryContextSwitchTo(old);
/* initialize vacuum cleaner */
vc_init();
/* vacuum the database */
if (vacrel)
vc_vacuum(&VacRel, analyze, va_cols);
else
vc_vacuum(NULL, analyze, NIL);
PortalDestroy(&vc_portal);
/* clean up */
vc_shutdown();
}
/*
* vc_init(), vc_shutdown() -- start up and shut down the vacuum cleaner.
*
* We run exactly one vacuum cleaner at a time. We use the file system
* to guarantee an exclusive lock on vacuuming, since a single vacuum
* cleaner instantiation crosses transaction boundaries, and we'd lose
* postgres-style locks at the end of every transaction.
*
* The strangeness with committing and starting transactions in the
* init and shutdown routines is due to the fact that the vacuum cleaner
* is invoked via a sql command, and so is already executing inside
* a transaction. We need to leave ourselves in a predictable state
* on entry and exit to the vacuum cleaner. We commit the transaction
* started in PostgresMain() inside vc_init(), and start one in
* vc_shutdown() to match the commit waiting for us back in
* PostgresMain().
*/
static void
vc_init()
{
int fd;
if ((fd = open("pg_vlock", O_CREAT | O_EXCL, 0600)) < 0)
{
elog(ERROR, "Can't create lock file. Is another vacuum cleaner running?\n\
\tIf not, you may remove the pg_vlock file in the %s\n\
\tdirectory", DatabasePath);
}
close(fd);
/*
* By here, exclusive open on the lock file succeeded. If we abort
* for any reason during vacuuming, we need to remove the lock file.
* This global variable is checked in the transaction manager on xact
* abort, and the routine vc_abort() is called if necessary.
*/
VacuumRunning = true;
/* matches the StartTransaction in PostgresMain() */
CommitTransactionCommand();
}
static void
vc_shutdown()
{
/* on entry, not in a transaction */
if (unlink("pg_vlock") < 0)
elog(ERROR, "vacuum: can't destroy lock file!");
/* okay, we're done */
VacuumRunning = false;
/* matches the CommitTransaction in PostgresMain() */
StartTransactionCommand();
}
void
vc_abort()
{
/* on abort, remove the vacuum cleaner lock file */
unlink("pg_vlock");
VacuumRunning = false;
}
/*
* vc_vacuum() -- vacuum the database.
*
* This routine builds a list of relations to vacuum, and then calls
* code that vacuums them one at a time. We are careful to vacuum each
* relation in a separate transaction in order to avoid holding too many
* locks at one time.
*/
static void
vc_vacuum(NameData *VacRelP, bool analyze, List *va_cols)
{
VRelList vrl,
cur;
/* get list of relations */
vrl = vc_getrels(VacRelP);
if (analyze && VacRelP == NULL && vrl != NULL)
vc_delhilowstats(InvalidOid, 0, NULL);
/* vacuum each heap relation */
for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
vc_vacone(cur->vrl_relid, analyze, va_cols);
vc_free(vrl);
}
static VRelList
vc_getrels(NameData *VacRelP)
{
Relation rel;
TupleDesc tupdesc;
HeapScanDesc scan;
HeapTuple tuple;
PortalVariableMemory portalmem;
MemoryContext old;
VRelList vrl,
cur;
Datum d;
char *rname;
char rkind;
bool n;
bool found = false;
ScanKeyData key;
StartTransactionCommand();
if (VacRelP->data)
{
ScanKeyEntryInitialize(&key, 0x0, Anum_pg_class_relname,
F_NAMEEQ,
PointerGetDatum(VacRelP->data));
}
else
{
ScanKeyEntryInitialize(&key, 0x0, Anum_pg_class_relkind,
F_CHAREQ, CharGetDatum('r'));
}
portalmem = PortalGetVariableMemory(vc_portal);
vrl = cur = (VRelList) NULL;
rel = heap_openr(RelationRelationName);
tupdesc = RelationGetTupleDescriptor(rel);
scan = heap_beginscan(rel, false, SnapshotNow, 1, &key);
while (HeapTupleIsValid(tuple = heap_getnext(scan, 0)))
{
found = true;
d = heap_getattr(tuple, Anum_pg_class_relname, tupdesc, &n);
rname = (char *) d;
/*
* don't vacuum large objects for now - something breaks when we
* do
*/
if ((strlen(rname) >= 5) && rname[0] == 'x' &&
rname[1] == 'i' && rname[2] == 'n' &&
(rname[3] == 'v' || rname[3] == 'x') &&
rname[4] >= '0' && rname[4] <= '9')
{
elog(NOTICE, "Rel %s: can't vacuum LargeObjects now",
rname);
continue;
}
d = heap_getattr(tuple, Anum_pg_class_relkind, tupdesc, &n);
rkind = DatumGetChar(d);
/* skip system relations */
if (rkind != 'r')
{
elog(NOTICE, "Vacuum: can not process index and certain system tables");
continue;
}
/* get a relation list entry for this guy */
old = MemoryContextSwitchTo((MemoryContext) portalmem);
if (vrl == (VRelList) NULL)
vrl = cur = (VRelList) palloc(sizeof(VRelListData));
else
{
cur->vrl_next = (VRelList) palloc(sizeof(VRelListData));
cur = cur->vrl_next;
}
MemoryContextSwitchTo(old);
cur->vrl_relid = tuple->t_oid;
cur->vrl_next = (VRelList) NULL;
}
if (found == false)
elog(NOTICE, "Vacuum: table not found");
heap_endscan(scan);
heap_close(rel);
CommitTransactionCommand();
return (vrl);
}
/*
* vc_vacone() -- vacuum one heap relation
*
* This routine vacuums a single heap, cleans out its indices, and
* updates its statistics num_pages and num_tuples statistics.
*
* Doing one heap at a time incurs extra overhead, since we need to
* check that the heap exists again just before we vacuum it. The
* reason that we do this is so that vacuuming can be spread across
* many small transactions. Otherwise, two-phase locking would require
* us to lock the entire database during one pass of the vacuum cleaner.
*/
static void
vc_vacone(Oid relid, bool analyze, List *va_cols)
{
Relation rel;
TupleDesc tupdesc;
HeapTuple tuple,
typetuple;
Relation onerel;
VPageListData vacuum_pages; /* List of pages to vacuum and/or clean
* indices */
VPageListData fraged_pages; /* List of pages with space enough for
* re-using */
VPageDescr *vpp;
Relation *Irel;
int32 nindices,
i;
VRelStats *vacrelstats;
StartTransactionCommand();
rel = heap_openr(RelationRelationName);
tupdesc = RelationGetTupleDescriptor(rel);
/*
* Race condition -- if the pg_class tuple has gone away since the
* last time we saw it, we don't need to vacuum it.
*/
tuple = SearchSysCacheTuple(RELOID,
ObjectIdGetDatum(relid),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
{
heap_close(rel);
CommitTransactionCommand();
return;
}
/* now open the class and vacuum it */
onerel = heap_open(relid);
vacrelstats = (VRelStats *) palloc(sizeof(VRelStats));
vacrelstats->relid = relid;
vacrelstats->num_pages = vacrelstats->num_tuples = 0;
vacrelstats->hasindex = false;
if (analyze && !IsSystemRelationName((RelationGetRelationName(onerel))->data))
{
int attr_cnt,
*attnums = NULL;
AttributeTupleForm *attr;
attr_cnt = onerel->rd_att->natts;
attr = onerel->rd_att->attrs;
if (va_cols != NIL)
{
int tcnt = 0;
List *le;
if (length(va_cols) > attr_cnt)
elog(ERROR, "vacuum: too many attributes specified for relation %s",
(RelationGetRelationName(onerel))->data);
attnums = (int *) palloc(attr_cnt * sizeof(int));
foreach(le, va_cols)
{
char *col = (char *) lfirst(le);
for (i = 0; i < attr_cnt; i++)
{
if (namestrcmp(&(attr[i]->attname), col) == 0)
break;
}
if (i < attr_cnt) /* found */
attnums[tcnt++] = i;
else
{
elog(ERROR, "vacuum: there is no attribute %s in %s",
col, (RelationGetRelationName(onerel))->data);
}
}
attr_cnt = tcnt;
}
vacrelstats->vacattrstats =
(VacAttrStats *) palloc(attr_cnt * sizeof(VacAttrStats));
for (i = 0; i < attr_cnt; i++)
{
Operator func_operator;
OperatorTupleForm pgopform;
VacAttrStats *stats;
stats = &vacrelstats->vacattrstats[i];
stats->attr = palloc(ATTRIBUTE_TUPLE_SIZE);
memmove(stats->attr, attr[((attnums) ? attnums[i] : i)], ATTRIBUTE_TUPLE_SIZE);
stats->best = stats->guess1 = stats->guess2 = 0;
stats->max = stats->min = 0;
stats->best_len = stats->guess1_len = stats->guess2_len = 0;
stats->max_len = stats->min_len = 0;
stats->initialized = false;
stats->best_cnt = stats->guess1_cnt = stats->guess1_hits = stats->guess2_hits = 0;
stats->max_cnt = stats->min_cnt = stats->null_cnt = stats->nonnull_cnt = 0;
func_operator = oper("=", stats->attr->atttypid, stats->attr->atttypid, true);
if (func_operator != NULL)
{
pgopform = (OperatorTupleForm) GETSTRUCT(func_operator);
fmgr_info(pgopform->oprcode, &(stats->f_cmpeq));
}
else
stats->f_cmpeq.fn_addr = NULL;
func_operator = oper("<", stats->attr->atttypid, stats->attr->atttypid, true);
if (func_operator != NULL)
{
pgopform = (OperatorTupleForm) GETSTRUCT(func_operator);
fmgr_info(pgopform->oprcode, &(stats->f_cmplt));
}
else
stats->f_cmplt.fn_addr = NULL;
func_operator = oper(">", stats->attr->atttypid, stats->attr->atttypid, true);
if (func_operator != NULL)
{
pgopform = (OperatorTupleForm) GETSTRUCT(func_operator);
fmgr_info(pgopform->oprcode, &(stats->f_cmpgt));
}
else
stats->f_cmpgt.fn_addr = NULL;
typetuple = SearchSysCacheTuple(TYPOID,
ObjectIdGetDatum(stats->attr->atttypid),
0, 0, 0);
if (HeapTupleIsValid(typetuple))
stats->outfunc = ((TypeTupleForm) GETSTRUCT(typetuple))->typoutput;
else
stats->outfunc = InvalidOid;
}
vacrelstats->va_natts = attr_cnt;
vc_delhilowstats(relid, ((attnums) ? attr_cnt : 0), attnums);
if (attnums)
pfree(attnums);
}
else
{
vacrelstats->va_natts = 0;
vacrelstats->vacattrstats = (VacAttrStats *) NULL;
}
/* we require the relation to be locked until the indices are cleaned */
RelationSetLockForWrite(onerel);
/* scan it */
vacuum_pages.vpl_num_pages = fraged_pages.vpl_num_pages = 0;
vc_scanheap(vacrelstats, onerel, &vacuum_pages, &fraged_pages);
/* Now open indices */
Irel = (Relation *) NULL;
vc_getindices(vacrelstats->relid, &nindices, &Irel);
if (nindices > 0)
vacrelstats->hasindex = true;
else
vacrelstats->hasindex = false;
/* Clean/scan index relation(s) */
if (Irel != (Relation *) NULL)
{
if (vacuum_pages.vpl_num_pages > 0)
{
for (i = 0; i < nindices; i++)
vc_vaconeind(&vacuum_pages, Irel[i], vacrelstats->num_tuples);
}
else
/* just scan indices to update statistic */
{
for (i = 0; i < nindices; i++)
vc_scanoneind(Irel[i], vacrelstats->num_tuples);
}
}
if (fraged_pages.vpl_num_pages > 0) /* Try to shrink heap */
vc_rpfheap(vacrelstats, onerel, &vacuum_pages, &fraged_pages, nindices, Irel);
else
{
if (Irel != (Relation *) NULL)
vc_clsindices(nindices, Irel);
if (vacuum_pages.vpl_num_pages > 0)/* Clean pages from vacuum_pages list */
vc_vacheap(vacrelstats, onerel, &vacuum_pages);
}
/* ok - free vacuum_pages list of reapped pages */
if (vacuum_pages.vpl_num_pages > 0)
{
vpp = vacuum_pages.vpl_pagedesc;
for (i = 0; i < vacuum_pages.vpl_num_pages; i++, vpp++)
pfree(*vpp);
pfree(vacuum_pages.vpl_pagedesc);
if (fraged_pages.vpl_num_pages > 0)
pfree(fraged_pages.vpl_pagedesc);
}
/* all done with this class */
heap_close(onerel);
heap_close(rel);
/* update statistics in pg_class */
vc_updstats(vacrelstats->relid, vacrelstats->num_pages, vacrelstats->num_tuples,
vacrelstats->hasindex, vacrelstats);
/* next command frees attribute stats */
CommitTransactionCommand();
}
/*
* vc_scanheap() -- scan an open heap relation
*
* This routine sets commit times, constructs vacuum_pages list of
* empty/uninitialized pages and pages with dead tuples and
* ~LP_USED line pointers, constructs fraged_pages list of pages
* appropriate for purposes of shrinking and maintains statistics
* on the number of live tuples in a heap.
*/
static void
vc_scanheap(VRelStats *vacrelstats, Relation onerel,
VPageList vacuum_pages, VPageList fraged_pages)
{
int nblocks,
blkno;
ItemId itemid;
ItemPointer itemptr;
Buffer buf;
HeapTuple tuple;
Page page,
tempPage = NULL;
OffsetNumber offnum,
maxoff;
bool pgchanged,
tupgone,
dobufrel,
notup;
char *relname;
VPageDescr vpc,
vp;
uint32 tups_vacuumed,
num_tuples,
nunused,
ncrash,
empty_pages,
new_pages,
changed_pages,
empty_end_pages;
Size free_size,
usable_free_size;
Size min_tlen = MAXTUPLEN;
Size max_tlen = 0;
int32 i;
struct rusage ru0,
ru1;
bool do_shrinking = true;
getrusage(RUSAGE_SELF, &ru0);
tups_vacuumed = num_tuples = nunused = ncrash = empty_pages =
new_pages = changed_pages = empty_end_pages = 0;
free_size = usable_free_size = 0;
relname = (RelationGetRelationName(onerel))->data;
nblocks = RelationGetNumberOfBlocks(onerel);
vpc = (VPageDescr) palloc(sizeof(VPageDescrData) + MaxOffsetNumber * sizeof(OffsetNumber));
vpc->vpd_offsets_used = 0;
elog(MESSAGE_LEVEL, "--Relation %s--", relname);
for (blkno = 0; blkno < nblocks; blkno++)
{
buf = ReadBuffer(onerel, blkno);
page = BufferGetPage(buf);
vpc->vpd_blkno = blkno;
vpc->vpd_offsets_free = 0;
if (PageIsNew(page))
{
elog(NOTICE, "Rel %s: Uninitialized page %u - fixing",
relname, blkno);
PageInit(page, BufferGetPageSize(buf), 0);
vpc->vpd_free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
free_size += (vpc->vpd_free - sizeof(ItemIdData));
new_pages++;
empty_end_pages++;
vc_reappage(vacuum_pages, vpc);
WriteBuffer(buf);
continue;
}
if (PageIsEmpty(page))
{
vpc->vpd_free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
free_size += (vpc->vpd_free - sizeof(ItemIdData));
empty_pages++;
empty_end_pages++;
vc_reappage(vacuum_pages, vpc);
ReleaseBuffer(buf);
continue;
}
pgchanged = false;
notup = true;
maxoff = PageGetMaxOffsetNumber(page);
for (offnum = FirstOffsetNumber;
offnum <= maxoff;
offnum = OffsetNumberNext(offnum))
{
itemid = PageGetItemId(page, offnum);
/*
* Collect un-used items too - it's possible to have indices
* pointing here after crash.
*/
if (!ItemIdIsUsed(itemid))
{
vpc->vpd_offsets[vpc->vpd_offsets_free++] = offnum;
nunused++;
continue;
}
tuple = (HeapTuple) PageGetItem(page, itemid);
tupgone = false;
if (!(tuple->t_infomask & HEAP_XMIN_COMMITTED))
{
if (tuple->t_infomask & HEAP_XMIN_INVALID)
tupgone = true;
else
{
if (TransactionIdDidAbort(tuple->t_xmin))
tupgone = true;
else if (TransactionIdDidCommit(tuple->t_xmin))
{
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
pgchanged = true;
}
else if (!TransactionIdIsInProgress(tuple->t_xmin))
{
/*
* Not Aborted, Not Committed, Not in Progress -
* so it's from crashed process. - vadim 11/26/96
*/
ncrash++;
tupgone = true;
}
else
{
elog(NOTICE, "Rel %s: TID %u/%u: InsertTransactionInProgress %u - can't shrink relation",
relname, blkno, offnum, tuple->t_xmin);
do_shrinking = false;
}
}
}
/*
* here we are concerned about tuples with xmin committed and
* xmax unknown or committed
*/
if (tuple->t_infomask & HEAP_XMIN_COMMITTED &&
!(tuple->t_infomask & HEAP_XMAX_INVALID))
{
if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
tupgone = true;
else if (TransactionIdDidAbort(tuple->t_xmax))
{
tuple->t_infomask |= HEAP_XMAX_INVALID;
pgchanged = true;
}
else if (TransactionIdDidCommit(tuple->t_xmax))
tupgone = true;
else if (!TransactionIdIsInProgress(tuple->t_xmax))
{
/*
* Not Aborted, Not Committed, Not in Progress - so it
* from crashed process. - vadim 06/02/97
*/
tuple->t_infomask |= HEAP_XMAX_INVALID;;
pgchanged = true;
}
else
{
elog(NOTICE, "Rel %s: TID %u/%u: DeleteTransactionInProgress %u - can't shrink relation",
relname, blkno, offnum, tuple->t_xmax);
do_shrinking = false;
}
}
/*
* It's possibly! But from where it comes ? And should we fix
* it ? - vadim 11/28/96
*/
itemptr = &(tuple->t_ctid);
if (!ItemPointerIsValid(itemptr) ||
BlockIdGetBlockNumber(&(itemptr->ip_blkid)) != blkno)
{
elog(NOTICE, "Rel %s: TID %u/%u: TID IN TUPLEHEADER %u/%u IS NOT THE SAME. TUPGONE %d.",
relname, blkno, offnum,
BlockIdGetBlockNumber(&(itemptr->ip_blkid)),
itemptr->ip_posid, tupgone);
}
/*
* Other checks...
*/
if (tuple->t_len != itemid->lp_len)
{
elog(NOTICE, "Rel %s: TID %u/%u: TUPLE_LEN IN PAGEHEADER %u IS NOT THE SAME AS IN TUPLEHEADER %u. TUPGONE %d.",
relname, blkno, offnum,
itemid->lp_len, tuple->t_len, tupgone);
}
if (!OidIsValid(tuple->t_oid))
{
elog(NOTICE, "Rel %s: TID %u/%u: OID IS INVALID. TUPGONE %d.",
relname, blkno, offnum, tupgone);
}
if (tupgone)
{
ItemId lpp;
if (tempPage == (Page) NULL)
{
Size pageSize;
pageSize = PageGetPageSize(page);
tempPage = (Page) palloc(pageSize);
memmove(tempPage, page, pageSize);
}
lpp = &(((PageHeader) tempPage)->pd_linp[offnum - 1]);
/* mark it unused */
lpp->lp_flags &= ~LP_USED;
vpc->vpd_offsets[vpc->vpd_offsets_free++] = offnum;
tups_vacuumed++;
}
else
{
num_tuples++;
notup = false;
if (tuple->t_len < min_tlen)
min_tlen = tuple->t_len;
if (tuple->t_len > max_tlen)
max_tlen = tuple->t_len;
vc_attrstats(onerel, vacrelstats, tuple);
}
}
if (pgchanged)
{
WriteBuffer(buf);
dobufrel = false;
changed_pages++;
}
else
dobufrel = true;
if (tempPage != (Page) NULL)
{ /* Some tuples are gone */
PageRepairFragmentation(tempPage);
vpc->vpd_free = ((PageHeader) tempPage)->pd_upper - ((PageHeader) tempPage)->pd_lower;
free_size += vpc->vpd_free;
vc_reappage(vacuum_pages, vpc);
pfree(tempPage);
tempPage = (Page) NULL;
}
else if (vpc->vpd_offsets_free > 0)
{ /* there are only ~LP_USED line pointers */
vpc->vpd_free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
free_size += vpc->vpd_free;
vc_reappage(vacuum_pages, vpc);
}
if (dobufrel)
ReleaseBuffer(buf);
if (notup)
empty_end_pages++;
else
empty_end_pages = 0;
}
pfree(vpc);
/* save stats in the rel list for use later */
vacrelstats->num_tuples = num_tuples;
vacrelstats->num_pages = nblocks;
/* vacrelstats->natts = attr_cnt;*/
if (num_tuples == 0)
min_tlen = max_tlen = 0;
vacrelstats->min_tlen = min_tlen;
vacrelstats->max_tlen = max_tlen;
vacuum_pages->vpl_empty_end_pages = empty_end_pages;
fraged_pages->vpl_empty_end_pages = empty_end_pages;
/*
* Try to make fraged_pages keeping in mind that we can't use free space of
* "empty" end-pages and last page if it reapped.
*/
if (do_shrinking && vacuum_pages->vpl_num_pages - empty_end_pages > 0)
{
int nusf; /* blocks usefull for re-using */
nusf = vacuum_pages->vpl_num_pages - empty_end_pages;
if ((vacuum_pages->vpl_pagedesc[nusf - 1])->vpd_blkno == nblocks - empty_end_pages - 1)
nusf--;
for (i = 0; i < nusf; i++)
{
vp = vacuum_pages->vpl_pagedesc[i];
if (vc_enough_space(vp, min_tlen))
{
vc_vpinsert(fraged_pages, vp);
usable_free_size += vp->vpd_free;
}
}
}
getrusage(RUSAGE_SELF, &ru1);
elog(MESSAGE_LEVEL, "Pages %u: Changed %u, Reapped %u, Empty %u, New %u; \
Tup %u: Vac %u, Crash %u, UnUsed %u, MinLen %u, MaxLen %u; Re-using: Free/Avail. Space %u/%u; EndEmpty/Avail. Pages %u/%u. Elapsed %u/%u sec.",
nblocks, changed_pages, vacuum_pages->vpl_num_pages, empty_pages, new_pages,
num_tuples, tups_vacuumed, ncrash, nunused, min_tlen, max_tlen,
free_size, usable_free_size, empty_end_pages, fraged_pages->vpl_num_pages,
ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
} /* vc_scanheap */
/*
* vc_rpfheap() -- try to repaire relation' fragmentation
*
* This routine marks dead tuples as unused and tries re-use dead space
* by moving tuples (and inserting indices if needed). It constructs
* Nvpl list of free-ed pages (moved tuples) and clean indices
* for them after committing (in hack-manner - without losing locks
* and freeing memory!) current transaction. It truncates relation
* if some end-blocks are gone away.
*/
static void
vc_rpfheap(VRelStats *vacrelstats, Relation onerel,
VPageList vacuum_pages, VPageList fraged_pages, int nindices, Relation *Irel)
{
TransactionId myXID;
CommandId myCID;
Buffer buf,
cur_buffer;
int nblocks,
blkno;
Page page,
ToPage = NULL;
OffsetNumber offnum = 0,
maxoff = 0,
newoff,
max_offset;
ItemId itemid,
newitemid;
HeapTuple tuple,
newtup;
TupleDesc tupdesc = NULL;
Datum *idatum = NULL;
char *inulls = NULL;
InsertIndexResult iresult;
VPageListData Nvpl;
VPageDescr cur_page = NULL,
last_fraged_page,
last_vacuum_page,
vpc,
*vpp;
int cur_item = 0;
IndDesc *Idesc,
*idcur;
int last_fraged_block,
last_vacuum_block,
i;
Size tuple_len;
int num_moved,
num_fraged_pages,
vacuumed_pages;
int checked_moved,
num_tuples;
bool isempty,
dowrite;
struct rusage ru0,
ru1;
getrusage(RUSAGE_SELF, &ru0);
myXID = GetCurrentTransactionId();
myCID = GetCurrentCommandId();
if (Irel != (Relation *) NULL) /* preparation for index' inserts */
{
vc_mkindesc(onerel, nindices, Irel, &Idesc);
tupdesc = RelationGetTupleDescriptor(onerel);
idatum = (Datum *) palloc(INDEX_MAX_KEYS * sizeof(*idatum));
inulls = (char *) palloc(INDEX_MAX_KEYS * sizeof(*inulls));
}
Nvpl.vpl_num_pages = 0;
num_fraged_pages = fraged_pages->vpl_num_pages;
last_fraged_page = fraged_pages->vpl_pagedesc[num_fraged_pages - 1];
last_fraged_block = last_fraged_page->vpd_blkno;
Assert(vacuum_pages->vpl_num_pages > vacuum_pages->vpl_empty_end_pages);
vacuumed_pages = vacuum_pages->vpl_num_pages - vacuum_pages->vpl_empty_end_pages;
last_vacuum_page = vacuum_pages->vpl_pagedesc[vacuumed_pages - 1];
last_vacuum_block = last_vacuum_page->vpd_blkno;
Assert(last_vacuum_block >= last_fraged_block);
cur_buffer = InvalidBuffer;
num_moved = 0;
vpc = (VPageDescr) palloc(sizeof(VPageDescrData) + MaxOffsetNumber * sizeof(OffsetNumber));
vpc->vpd_offsets_used = vpc->vpd_offsets_free = 0;
nblocks = vacrelstats->num_pages;
for (blkno = nblocks - vacuum_pages->vpl_empty_end_pages - 1;; blkno--)
{
/* if it's reapped page and it was used by me - quit */
if (blkno == last_fraged_block && last_fraged_page->vpd_offsets_used > 0)
break;
buf = ReadBuffer(onerel, blkno);
page = BufferGetPage(buf);
vpc->vpd_offsets_free = 0;
isempty = PageIsEmpty(page);
dowrite = false;
if (blkno == last_vacuum_block) /* it's reapped page */
{
if (last_vacuum_page->vpd_offsets_free > 0) /* there are dead tuples */
{ /* on this page - clean */
Assert(!isempty);
vc_vacpage(page, last_vacuum_page);
dowrite = true;
}
else
Assert(isempty);
--vacuumed_pages;
Assert(vacuumed_pages > 0);
/* get prev reapped page from vacuum_pages */
last_vacuum_page = vacuum_pages->vpl_pagedesc[vacuumed_pages - 1];
last_vacuum_block = last_vacuum_page->vpd_blkno;
if (blkno == last_fraged_block) /* this page in fraged_pages too */
{
--num_fraged_pages;
Assert(num_fraged_pages > 0);
Assert(last_fraged_page->vpd_offsets_used == 0);
/* get prev reapped page from fraged_pages */
last_fraged_page = fraged_pages->vpl_pagedesc[num_fraged_pages - 1];
last_fraged_block = last_fraged_page->vpd_blkno;
}
Assert(last_fraged_block <= last_vacuum_block);
if (isempty)
{
ReleaseBuffer(buf);
continue;
}
}
else
Assert(!isempty);
vpc->vpd_blkno = blkno;
maxoff = PageGetMaxOffsetNumber(page);
for (offnum = FirstOffsetNumber;
offnum <= maxoff;
offnum = OffsetNumberNext(offnum))
{
itemid = PageGetItemId(page, offnum);
if (!ItemIdIsUsed(itemid))
continue;
tuple = (HeapTuple) PageGetItem(page, itemid);
tuple_len = tuple->t_len;
/* try to find new page for this tuple */
if (cur_buffer == InvalidBuffer ||
!vc_enough_space(cur_page, tuple_len))
{
if (cur_buffer != InvalidBuffer)
{
WriteBuffer(cur_buffer);
cur_buffer = InvalidBuffer;
/*
* If no one tuple can't be added to this page -
* remove page from fraged_pages. - vadim 11/27/96
*
* But we can't remove last page - this is our
* "show-stopper" !!! - vadim 02/25/98
*/
if (cur_page != last_fraged_page &&
!vc_enough_space(cur_page, vacrelstats->min_tlen))
{
Assert(num_fraged_pages > cur_item + 1);
memmove(fraged_pages->vpl_pagedesc + cur_item,
fraged_pages->vpl_pagedesc + cur_item + 1,
sizeof(VPageDescr *) * (num_fraged_pages - cur_item - 1));
num_fraged_pages--;
Assert(last_fraged_page == fraged_pages->vpl_pagedesc[num_fraged_pages - 1]);
}
}
for (i = 0; i < num_fraged_pages; i++)
{
if (vc_enough_space(fraged_pages->vpl_pagedesc[i], tuple_len))
break;
}
if (i == num_fraged_pages)
break; /* can't move item anywhere */
cur_item = i;
cur_page = fraged_pages->vpl_pagedesc[cur_item];
cur_buffer = ReadBuffer(onerel, cur_page->vpd_blkno);
ToPage = BufferGetPage(cur_buffer);
/* if this page was not used before - clean it */
if (!PageIsEmpty(ToPage) && cur_page->vpd_offsets_used == 0)
vc_vacpage(ToPage, cur_page);
}
/* copy tuple */
newtup = (HeapTuple) palloc(tuple_len);
memmove((char *) newtup, (char *) tuple, tuple_len);
/* store transaction information */
TransactionIdStore(myXID, &(newtup->t_xmin));
newtup->t_cmin = myCID;
StoreInvalidTransactionId(&(newtup->t_xmax));
/* set xmin to unknown and xmax to invalid */
newtup->t_infomask &= ~(HEAP_XACT_MASK);
newtup->t_infomask |= HEAP_XMAX_INVALID;
/* add tuple to the page */
newoff = PageAddItem(ToPage, (Item) newtup, tuple_len,
InvalidOffsetNumber, LP_USED);
if (newoff == InvalidOffsetNumber)
{
elog(ERROR, "\
failed to add item with len = %u to page %u (free space %u, nusd %u, noff %u)",
tuple_len, cur_page->vpd_blkno, cur_page->vpd_free,
cur_page->vpd_offsets_used, cur_page->vpd_offsets_free);
}
newitemid = PageGetItemId(ToPage, newoff);
pfree(newtup);
newtup = (HeapTuple) PageGetItem(ToPage, newitemid);
ItemPointerSet(&(newtup->t_ctid), cur_page->vpd_blkno, newoff);
/* now logically delete end-tuple */
TransactionIdStore(myXID, &(tuple->t_xmax));
tuple->t_cmax = myCID;
/* set xmax to unknown */
tuple->t_infomask &= ~(HEAP_XMAX_INVALID | HEAP_XMAX_COMMITTED);
cur_page->vpd_offsets_used++;
num_moved++;
cur_page->vpd_free = ((PageHeader) ToPage)->pd_upper - ((PageHeader) ToPage)->pd_lower;
vpc->vpd_offsets[vpc->vpd_offsets_free++] = offnum;
/* insert index' tuples if needed */
if (Irel != (Relation *) NULL)
{
for (i = 0, idcur = Idesc; i < nindices; i++, idcur++)
{
FormIndexDatum(idcur->natts,
(AttrNumber *) &(idcur->tform->indkey[0]),
newtup,
tupdesc,
idatum,
inulls,
idcur->finfoP);
iresult = index_insert(Irel[i],
idatum,
inulls,
&(newtup->t_ctid),
onerel);
if (iresult)
pfree(iresult);
}
}
} /* walk along page */
if (vpc->vpd_offsets_free > 0) /* some tuples were moved */
{
vc_reappage(&Nvpl, vpc);
WriteBuffer(buf);
}
else if (dowrite)
WriteBuffer(buf);
else
ReleaseBuffer(buf);
if (offnum <= maxoff)
break; /* some item(s) left */
} /* walk along relation */
blkno++; /* new number of blocks */
if (cur_buffer != InvalidBuffer)
{
Assert(num_moved > 0);
WriteBuffer(cur_buffer);
}
if (num_moved > 0)
{
/*
* We have to commit our tuple' movings before we'll truncate
* relation, but we shouldn't lose our locks. And so - quick hack:
* flush buffers and record status of current transaction as
* committed, and continue. - vadim 11/13/96
*/
FlushBufferPool(!TransactionFlushEnabled());
TransactionIdCommit(myXID);
FlushBufferPool(!TransactionFlushEnabled());
}
/*
* Clean uncleaned reapped pages from vacuum_pages list and set xmin committed
* for inserted tuples
*/
checked_moved = 0;
for (i = 0, vpp = vacuum_pages->vpl_pagedesc; i < vacuumed_pages; i++, vpp++)
{
Assert((*vpp)->vpd_blkno < blkno);
buf = ReadBuffer(onerel, (*vpp)->vpd_blkno);
page = BufferGetPage(buf);
if ((*vpp)->vpd_offsets_used == 0) /* this page was not used */
{
/*
* noff == 0 in empty pages only - such pages should be
* re-used
*/
Assert((*vpp)->vpd_offsets_free > 0);
vc_vacpage(page, *vpp);
}
else
/* this page was used */
{
num_tuples = 0;
max_offset = PageGetMaxOffsetNumber(page);
for (newoff = FirstOffsetNumber;
newoff <= max_offset;
newoff = OffsetNumberNext(newoff))
{
itemid = PageGetItemId(page, newoff);
if (!ItemIdIsUsed(itemid))
continue;
tuple = (HeapTuple) PageGetItem(page, itemid);
if (TransactionIdEquals((TransactionId) tuple->t_xmin, myXID))
{
tuple->t_infomask |= HEAP_XMIN_COMMITTED;
num_tuples++;
}
}
Assert((*vpp)->vpd_offsets_used == num_tuples);
checked_moved += num_tuples;
}
WriteBuffer(buf);
}
Assert(num_moved == checked_moved);
getrusage(RUSAGE_SELF, &ru1);
elog(MESSAGE_LEVEL, "Rel %s: Pages: %u --> %u; Tuple(s) moved: %u. \
Elapsed %u/%u sec.",
(RelationGetRelationName(onerel))->data,
nblocks, blkno, num_moved,
ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
if (Nvpl.vpl_num_pages > 0)
{
/* vacuum indices again if needed */
if (Irel != (Relation *) NULL)
{
VPageDescr *vpleft,
*vpright,
vpsave;
/* re-sort Nvpl.vpl_pagedesc */
for (vpleft = Nvpl.vpl_pagedesc,
vpright = Nvpl.vpl_pagedesc + Nvpl.vpl_num_pages - 1;
vpleft < vpright; vpleft++, vpright--)
{
vpsave = *vpleft;
*vpleft = *vpright;
*vpright = vpsave;
}
for (i = 0; i < nindices; i++)
vc_vaconeind(&Nvpl, Irel[i], vacrelstats->num_tuples);
}
/*
* clean moved tuples from last page in Nvpl list if some tuples
* left there
*/
if (vpc->vpd_offsets_free > 0 && offnum <= maxoff)
{
Assert(vpc->vpd_blkno == blkno - 1);
buf = ReadBuffer(onerel, vpc->vpd_blkno);
page = BufferGetPage(buf);
num_tuples = 0;
maxoff = offnum;
for (offnum = FirstOffsetNumber;
offnum < maxoff;
offnum = OffsetNumberNext(offnum))
{
itemid = PageGetItemId(page, offnum);
if (!ItemIdIsUsed(itemid))
continue;
tuple = (HeapTuple) PageGetItem(page, itemid);
Assert(TransactionIdEquals((TransactionId) tuple->t_xmax, myXID));
itemid->lp_flags &= ~LP_USED;
num_tuples++;
}
Assert(vpc->vpd_offsets_free == num_tuples);
PageRepairFragmentation(page);
WriteBuffer(buf);
}
/* now - free new list of reapped pages */
vpp = Nvpl.vpl_pagedesc;
for (i = 0; i < Nvpl.vpl_num_pages; i++, vpp++)
pfree(*vpp);
pfree(Nvpl.vpl_pagedesc);
}
/* truncate relation */
if (blkno < nblocks)
{
i = BlowawayRelationBuffers(onerel, blkno);
if (i < 0)
elog(FATAL, "VACUUM (vc_rpfheap): BlowawayRelationBuffers returned %d", i);
blkno = smgrtruncate(DEFAULT_SMGR, onerel, blkno);
Assert(blkno >= 0);
vacrelstats->num_pages = blkno; /* set new number of blocks */
}
if (Irel != (Relation *) NULL) /* pfree index' allocations */
{
pfree(Idesc);
pfree(idatum);
pfree(inulls);
vc_clsindices(nindices, Irel);
}
pfree(vpc);
} /* vc_rpfheap */
/*
* vc_vacheap() -- free dead tuples
*
* This routine marks dead tuples as unused and truncates relation
* if there are "empty" end-blocks.
*/
static void
vc_vacheap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages)
{
Buffer buf;
Page page;
VPageDescr *vpp;
int nblocks;
int i;
nblocks = vacuum_pages->vpl_num_pages;
nblocks -= vacuum_pages->vpl_empty_end_pages;/* nothing to do with them */
for (i = 0, vpp = vacuum_pages->vpl_pagedesc; i < nblocks; i++, vpp++)
{
if ((*vpp)->vpd_offsets_free > 0)
{
buf = ReadBuffer(onerel, (*vpp)->vpd_blkno);
page = BufferGetPage(buf);
vc_vacpage(page, *vpp);
WriteBuffer(buf);
}
}
/* truncate relation if there are some empty end-pages */
if (vacuum_pages->vpl_empty_end_pages > 0)
{
Assert(vacrelstats->num_pages >= vacuum_pages->vpl_empty_end_pages);
nblocks = vacrelstats->num_pages - vacuum_pages->vpl_empty_end_pages;
elog(MESSAGE_LEVEL, "Rel %s: Pages: %u --> %u.",
(RelationGetRelationName(onerel))->data,
vacrelstats->num_pages, nblocks);
/*
* we have to flush "empty" end-pages (if changed, but who knows
* it) before truncation
*/
FlushBufferPool(!TransactionFlushEnabled());
i = BlowawayRelationBuffers(onerel, nblocks);
if (i < 0)
elog(FATAL, "VACUUM (vc_vacheap): BlowawayRelationBuffers returned %d", i);
nblocks = smgrtruncate(DEFAULT_SMGR, onerel, nblocks);
Assert(nblocks >= 0);
vacrelstats->num_pages = nblocks; /* set new number of blocks */
}
} /* vc_vacheap */
/*
* vc_vacpage() -- free dead tuples on a page
* and repaire its fragmentation.
*/
static void
vc_vacpage(Page page, VPageDescr vpd)
{
ItemId itemid;
int i;
Assert(vpd->vpd_offsets_used == 0);
for (i = 0; i < vpd->vpd_offsets_free; i++)
{
itemid = &(((PageHeader) page)->pd_linp[vpd->vpd_offsets[i] - 1]);
itemid->lp_flags &= ~LP_USED;
}
PageRepairFragmentation(page);
} /* vc_vacpage */
/*
* _vc_scanoneind() -- scan one index relation to update statistic.
*
*/
static void
vc_scanoneind(Relation indrel, int num_tuples)
{
RetrieveIndexResult res;
IndexScanDesc iscan;
int nitups;
int nipages;
struct rusage ru0,
ru1;
getrusage(RUSAGE_SELF, &ru0);
/* walk through the entire index */
iscan = index_beginscan(indrel, false, 0, (ScanKey) NULL);
nitups = 0;
while ((res = index_getnext(iscan, ForwardScanDirection))
!= (RetrieveIndexResult) NULL)
{
nitups++;
pfree(res);
}
index_endscan(iscan);
/* now update statistics in pg_class */
nipages = RelationGetNumberOfBlocks(indrel);
vc_updstats(RelationGetRelid(indrel), nipages, nitups, false, NULL);
getrusage(RUSAGE_SELF, &ru1);
elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u. Elapsed %u/%u sec.",
indrel->rd_rel->relname.data, nipages, nitups,
ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
if (nitups != num_tuples)
elog(NOTICE, "Index %s: NUMBER OF INDEX' TUPLES (%u) IS NOT THE SAME AS HEAP' (%u)",
indrel->rd_rel->relname.data, nitups, num_tuples);
} /* vc_scanoneind */
/*
* vc_vaconeind() -- vacuum one index relation.
*
* Vpl is the VPageList of the heap we're currently vacuuming.
* It's locked. Indrel is an index relation on the vacuumed heap.
* We don't set locks on the index relation here, since the indexed
* access methods support locking at different granularities.
* We let them handle it.
*
* Finally, we arrange to update the index relation's statistics in
* pg_class.
*/
static void
vc_vaconeind(VPageList vpl, Relation indrel, int num_tuples)
{
RetrieveIndexResult res;
IndexScanDesc iscan;
ItemPointer heapptr;
int tups_vacuumed;
int num_index_tuples;
int num_pages;
VPageDescr vp;
struct rusage ru0,
ru1;
getrusage(RUSAGE_SELF, &ru0);
/* walk through the entire index */
iscan = index_beginscan(indrel, false, 0, (ScanKey) NULL);
tups_vacuumed = 0;
num_index_tuples = 0;
while ((res = index_getnext(iscan, ForwardScanDirection))
!= (RetrieveIndexResult) NULL)
{
heapptr = &res->heap_iptr;
if ((vp = vc_tidreapped(heapptr, vpl)) != (VPageDescr) NULL)
{
#if 0
elog(DEBUG, "<%x,%x> -> <%x,%x>",
ItemPointerGetBlockNumber(&(res->index_iptr)),
ItemPointerGetOffsetNumber(&(res->index_iptr)),
ItemPointerGetBlockNumber(&(res->heap_iptr)),
ItemPointerGetOffsetNumber(&(res->heap_iptr)));
#endif
if (vp->vpd_offsets_free == 0)
{ /* this is EmptyPage !!! */
elog(NOTICE, "Index %s: pointer to EmptyPage (blk %u off %u) - fixing",
indrel->rd_rel->relname.data,
vp->vpd_blkno, ItemPointerGetOffsetNumber(heapptr));
}
++tups_vacuumed;
index_delete(indrel, &res->index_iptr);
}
else
num_index_tuples++;
pfree(res);
}
index_endscan(iscan);
/* now update statistics in pg_class */
num_pages = RelationGetNumberOfBlocks(indrel);
vc_updstats(RelationGetRelid(indrel), num_pages, num_index_tuples, false, NULL);
getrusage(RUSAGE_SELF, &ru1);
elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u: Deleted %u. Elapsed %u/%u sec.",
indrel->rd_rel->relname.data, num_pages, num_index_tuples, tups_vacuumed,
ru1.ru_stime.tv_sec - ru0.ru_stime.tv_sec,
ru1.ru_utime.tv_sec - ru0.ru_utime.tv_sec);
if (num_index_tuples != num_tuples)
elog(NOTICE, "Index %s: NUMBER OF INDEX' TUPLES (%u) IS NOT THE SAME AS HEAP' (%u)",
indrel->rd_rel->relname.data, num_index_tuples, num_tuples);
} /* vc_vaconeind */
/*
* vc_tidreapped() -- is a particular tid reapped?
*
* vpl->VPageDescr_array is sorted in right order.
*/
static VPageDescr
vc_tidreapped(ItemPointer itemptr, VPageList vpl)
{
OffsetNumber ioffno;
OffsetNumber *voff;
VPageDescr vp,
*vpp;
VPageDescrData vpd;
vpd.vpd_blkno = ItemPointerGetBlockNumber(itemptr);
ioffno = ItemPointerGetOffsetNumber(itemptr);
vp = &vpd;
vpp = (VPageDescr *) vc_find_eq((char *) (vpl->vpl_pagedesc),
vpl->vpl_num_pages, sizeof(VPageDescr), (char *) &vp,
vc_cmp_blk);
if (vpp == (VPageDescr *) NULL)
return ((VPageDescr) NULL);
vp = *vpp;
/* ok - we are on true page */
if (vp->vpd_offsets_free == 0)
{ /* this is EmptyPage !!! */
return (vp);
}
voff = (OffsetNumber *) vc_find_eq((char *) (vp->vpd_offsets),
vp->vpd_offsets_free, sizeof(OffsetNumber), (char *) &ioffno,
vc_cmp_offno);
if (voff == (OffsetNumber *) NULL)
return ((VPageDescr) NULL);
return (vp);
} /* vc_tidreapped */
/*
* vc_attrstats() -- compute column statistics used by the optimzer
*
* We compute the column min, max, null and non-null counts.
* Plus we attempt to find the count of the value that occurs most
* frequently in each column
* These figures are used to compute the selectivity of the column
*
* We use a three-bucked cache to get the most frequent item
* The 'guess' buckets count hits. A cache miss causes guess1
* to get the most hit 'guess' item in the most recent cycle, and
* the new item goes into guess2. Whenever the total count of hits
* of a 'guess' entry is larger than 'best', 'guess' becomes 'best'.
*
* This method works perfectly for columns with unique values, and columns
* with only two unique values, plus nulls.
*
* It becomes less perfect as the number of unique values increases and
* their distribution in the table becomes more random.
*
*/
static void
vc_attrstats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple)
{
int i,
attr_cnt = vacrelstats->va_natts;
VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
TupleDesc tupDesc = onerel->rd_att;
Datum value;
bool isnull;
for (i = 0; i < attr_cnt; i++)
{
VacAttrStats *stats = &vacattrstats[i];
bool value_hit = true;
value = heap_getattr(tuple,
stats->attr->attnum, tupDesc, &isnull);
if (!VacAttrStatsEqValid(stats))
continue;
if (isnull)
stats->null_cnt++;
else
{
stats->nonnull_cnt++;
if (stats->initialized == false)
{
vc_bucketcpy(stats->attr, value, &stats->best, &stats->best_len);
/* best_cnt gets incremented later */
vc_bucketcpy(stats->attr, value, &stats->guess1, &stats->guess1_len);
stats->guess1_cnt = stats->guess1_hits = 1;
vc_bucketcpy(stats->attr, value, &stats->guess2, &stats->guess2_len);
stats->guess2_hits = 1;
if (VacAttrStatsLtGtValid(stats))
{
vc_bucketcpy(stats->attr, value, &stats->max, &stats->max_len);
vc_bucketcpy(stats->attr, value, &stats->min, &stats->min_len);
}
stats->initialized = true;
}
if (VacAttrStatsLtGtValid(stats))
{
if ((*fmgr_faddr(&stats->f_cmplt)) (value, stats->min))
{
vc_bucketcpy(stats->attr, value, &stats->min, &stats->min_len);
stats->min_cnt = 0;
}
if ((*fmgr_faddr(&stats->f_cmpgt)) (value, stats->max))
{
vc_bucketcpy(stats->attr, value, &stats->max, &stats->max_len);
stats->max_cnt = 0;
}
if ((*fmgr_faddr(&stats->f_cmpeq)) (value, stats->min))
stats->min_cnt++;
else if ((*fmgr_faddr(&stats->f_cmpeq)) (value, stats->max))
stats->max_cnt++;
}
if ((*fmgr_faddr(&stats->f_cmpeq)) (value, stats->best))
stats->best_cnt++;
else if ((*fmgr_faddr(&stats->f_cmpeq)) (value, stats->guess1))
{
stats->guess1_cnt++;
stats->guess1_hits++;
}
else if ((*fmgr_faddr(&stats->f_cmpeq)) (value, stats->guess2))
stats->guess2_hits++;
else
value_hit = false;
if (stats->guess2_hits > stats->guess1_hits)
{
swapDatum(stats->guess1, stats->guess2);
swapInt(stats->guess1_len, stats->guess2_len);
stats->guess1_cnt = stats->guess2_hits;
swapLong(stats->guess1_hits, stats->guess2_hits);
}
if (stats->guess1_cnt > stats->best_cnt)
{
swapDatum(stats->best, stats->guess1);
swapInt(stats->best_len, stats->guess1_len);
swapLong(stats->best_cnt, stats->guess1_cnt);
stats->guess1_hits = 1;
stats->guess2_hits = 1;
}
if (!value_hit)
{
vc_bucketcpy(stats->attr, value, &stats->guess2, &stats->guess2_len);
stats->guess1_hits = 1;
stats->guess2_hits = 1;
}
}
}
return;
}
/*
* vc_bucketcpy() -- update pg_class statistics for one relation
*
*/
static void
vc_bucketcpy(AttributeTupleForm attr, Datum value, Datum *bucket, int16 *bucket_len)
{
if (attr->attbyval && attr->attlen != -1)
*bucket = value;
else
{
int len = (attr->attlen != -1 ? attr->attlen : VARSIZE(value));
if (len > *bucket_len)
{
if (*bucket_len != 0)
pfree(DatumGetPointer(*bucket));
*bucket = PointerGetDatum(palloc(len));
*bucket_len = len;
}
memmove(DatumGetPointer(*bucket), DatumGetPointer(value), len);
}
}
/*
* vc_updstats() -- update pg_class statistics for one relation
*
* This routine works for both index and heap relation entries in
* pg_class. We violate no-overwrite semantics here by storing new
* values for num_tuples, num_pages, and hasindex directly in the pg_class
* tuple that's already on the page. The reason for this is that if
* we updated these tuples in the usual way, then every tuple in pg_class
* would be replaced every day. This would make planning and executing
* historical queries very expensive.
*/
static void
vc_updstats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats)
{
Relation rd,
ad,
sd;
HeapScanDesc scan;
HeapTuple rtup,
atup,
stup;
Form_pg_class pgcform;
ScanKeyData askey;
AttributeTupleForm attp;
Buffer buffer;
/*
* update number of tuples and number of pages in pg_class
*/
rtup = SearchSysCacheTuple(RELOID,
ObjectIdGetDatum(relid),
0, 0, 0);
if (!HeapTupleIsValid(rtup))
elog(ERROR, "pg_class entry for relid %d vanished during vacuuming",
relid);
rd = heap_openr(RelationRelationName);
/* get the buffer cache tuple */
rtup = heap_fetch(rd, SnapshotNow, &rtup->t_ctid, &buffer);
/* overwrite the existing statistics in the tuple */
vc_setpagelock(rd, ItemPointerGetBlockNumber(&rtup->t_ctid));
pgcform = (Form_pg_class) GETSTRUCT(rtup);
pgcform->reltuples = num_tuples;
pgcform->relpages = num_pages;
pgcform->relhasindex = hasindex;
if (vacrelstats != NULL && vacrelstats->va_natts > 0)
{
VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
int natts = vacrelstats->va_natts;
ad = heap_openr(AttributeRelationName);
sd = heap_openr(StatisticRelationName);
ScanKeyEntryInitialize(&askey, 0, Anum_pg_attribute_attrelid,
F_INT4EQ, relid);
scan = heap_beginscan(ad, false, SnapshotNow, 1, &askey);
while (HeapTupleIsValid(atup = heap_getnext(scan, 0)))
{
int i;
float32data selratio; /* average ratio of rows selected
* for a random constant */
VacAttrStats *stats;
Datum values[Natts_pg_statistic];
char nulls[Natts_pg_statistic];
attp = (AttributeTupleForm) GETSTRUCT(atup);
if (attp->attnum <= 0) /* skip system attributes for now, */
/* they are unique anyway */
continue;
for (i = 0; i < natts; i++)
{
if (attp->attnum == vacattrstats[i].attr->attnum)
break;
}
if (i >= natts)
continue;
stats = &(vacattrstats[i]);
/* overwrite the existing statistics in the tuple */
if (VacAttrStatsEqValid(stats))
{
vc_setpagelock(ad, ItemPointerGetBlockNumber(&atup->t_ctid));
if (stats->nonnull_cnt + stats->null_cnt == 0 ||
(stats->null_cnt <= 1 && stats->best_cnt == 1))
selratio = 0;
else if (VacAttrStatsLtGtValid(stats) && stats->min_cnt + stats->max_cnt == stats->nonnull_cnt)
{
double min_cnt_d = stats->min_cnt,
max_cnt_d = stats->max_cnt,
null_cnt_d = stats->null_cnt,
nonnullcnt_d = stats->nonnull_cnt; /* prevent overflow */
selratio = (min_cnt_d * min_cnt_d + max_cnt_d * max_cnt_d + null_cnt_d * null_cnt_d) /
(nonnullcnt_d + null_cnt_d) / (nonnullcnt_d + null_cnt_d);
}
else
{
double most = (double) (stats->best_cnt > stats->null_cnt ? stats->best_cnt : stats->null_cnt);
double total = ((double) stats->nonnull_cnt) + ((double) stats->null_cnt);
/*
* we assume count of other values are 20% of best
* count in table
*/
selratio = (most * most + 0.20 * most * (total - most)) / total / total;
}
if (selratio > 1.0)
selratio = 1.0;
attp->attdisbursion = selratio;
WriteNoReleaseBuffer(ItemPointerGetBlockNumber(&atup->t_ctid));
/* DO PG_STATISTIC INSERTS */
/*
* doing system relations, especially pg_statistic is a
* problem
*/
if (VacAttrStatsLtGtValid(stats) && stats->initialized /* &&
* !IsSystemRelationName(
*
pgcform->relname.data) */ )
{
FmgrInfo out_function;
char *out_string;
for (i = 0; i < Natts_pg_statistic; ++i)
nulls[i] = ' ';
/* ----------------
* initialize values[]
* ----------------
*/
i = 0;
values[i++] = (Datum) relid; /* 1 */
values[i++] = (Datum) attp->attnum; /* 2 */
values[i++] = (Datum) InvalidOid; /* 3 */
fmgr_info(stats->outfunc, &out_function);
out_string = (*fmgr_faddr(&out_function)) (stats->min, stats->attr->atttypid);
values[i++] = (Datum) fmgr(F_TEXTIN, out_string);
pfree(out_string);
out_string = (char *) (*fmgr_faddr(&out_function)) (stats->max, stats->attr->atttypid);
values[i++] = (Datum) fmgr(F_TEXTIN, out_string);
pfree(out_string);
stup = heap_formtuple(sd->rd_att, values, nulls);
/* ----------------
* insert the tuple in the relation and get the tuple's oid.
* ----------------
*/
heap_insert(sd, stup);
pfree(DatumGetPointer(values[3]));
pfree(DatumGetPointer(values[4]));
pfree(stup);
}
}
}
heap_endscan(scan);
heap_close(ad);
heap_close(sd);
}
/* XXX -- after write, should invalidate relcache in other backends */
WriteNoReleaseBuffer(ItemPointerGetBlockNumber(&rtup->t_ctid));
/*
* invalidating system relations confuses the function cache of
* pg_operator and pg_opclass, bjm
*/
if (!IsSystemRelationName(pgcform->relname.data))
RelationInvalidateHeapTuple(rd, rtup);
ReleaseBuffer(buffer);
heap_close(rd);
}
/*
* vc_delhilowstats() -- delete pg_statistics rows
*
*/
static void
vc_delhilowstats(Oid relid, int attcnt, int *attnums)
{
Relation pgstatistic;
HeapScanDesc scan;
HeapTuple tuple;
ScanKeyData key;
pgstatistic = heap_openr(StatisticRelationName);
if (relid != InvalidOid)
{
ScanKeyEntryInitialize(&key, 0x0, Anum_pg_statistic_starelid,
F_OIDEQ,
ObjectIdGetDatum(relid));
scan = heap_beginscan(pgstatistic, false, SnapshotNow, 1, &key);
}
else
scan = heap_beginscan(pgstatistic, false, SnapshotNow, 0, NULL);
while (HeapTupleIsValid(tuple = heap_getnext(scan, 0)))
{
if (attcnt > 0)
{
Form_pg_statistic pgs = (Form_pg_statistic) GETSTRUCT(tuple);
int i;
for (i = 0; i < attcnt; i++)
{
if (pgs->staattnum == attnums[i] + 1)
break;
}
if (i >= attcnt)
continue; /* don't delete it */
}
heap_delete(pgstatistic, &tuple->t_ctid);
}
heap_endscan(scan);
heap_close(pgstatistic);
}
static void
vc_setpagelock(Relation rel, BlockNumber blkno)
{
ItemPointerData itm;
ItemPointerSet(&itm, blkno, 1);
RelationSetLockForWritePage(rel, &itm);
}
/*
* vc_reappage() -- save a page on the array of reapped pages.
*
* As a side effect of the way that the vacuuming loop for a given
* relation works, higher pages come after lower pages in the array
* (and highest tid on a page is last).
*/
static void
vc_reappage(VPageList vpl, VPageDescr vpc)
{
VPageDescr newvpd;
/* allocate a VPageDescrData entry */
newvpd = (VPageDescr) palloc(sizeof(VPageDescrData) + vpc->vpd_offsets_free * sizeof(OffsetNumber));
/* fill it in */
if (vpc->vpd_offsets_free > 0)
memmove(newvpd->vpd_offsets, vpc->vpd_offsets, vpc->vpd_offsets_free * sizeof(OffsetNumber));
newvpd->vpd_blkno = vpc->vpd_blkno;
newvpd->vpd_free = vpc->vpd_free;
newvpd->vpd_offsets_used = vpc->vpd_offsets_used;
newvpd->vpd_offsets_free = vpc->vpd_offsets_free;
/* insert this page into vpl list */
vc_vpinsert(vpl, newvpd);
} /* vc_reappage */
static void
vc_vpinsert(VPageList vpl, VPageDescr vpnew)
{
/* allocate a VPageDescr entry if needed */
if (vpl->vpl_num_pages == 0)
vpl->vpl_pagedesc = (VPageDescr *) palloc(100 * sizeof(VPageDescr));
else if (vpl->vpl_num_pages % 100 == 0)
vpl->vpl_pagedesc = (VPageDescr *) repalloc(vpl->vpl_pagedesc, (vpl->vpl_num_pages + 100) * sizeof(VPageDescr));
vpl->vpl_pagedesc[vpl->vpl_num_pages] = vpnew;
(vpl->vpl_num_pages)++;
}
static void
vc_free(VRelList vrl)
{
VRelList p_vrl;
MemoryContext old;
PortalVariableMemory pmem;
pmem = PortalGetVariableMemory(vc_portal);
old = MemoryContextSwitchTo((MemoryContext) pmem);
while (vrl != (VRelList) NULL)
{
/* free rel list entry */
p_vrl = vrl;
vrl = vrl->vrl_next;
pfree(p_vrl);
}
MemoryContextSwitchTo(old);
}
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 */
static void
vc_getindices(Oid relid, int *nindices, Relation **Irel)
{
Relation pgindex;
Relation irel;
TupleDesc tupdesc;
HeapTuple tuple;
HeapScanDesc scan;
Datum d;
int i,
k;
bool n;
ScanKeyData key;
Oid *ioid;
*nindices = i = 0;
ioid = (Oid *) palloc(10 * sizeof(Oid));
/* prepare a heap scan on the pg_index relation */
pgindex = heap_openr(IndexRelationName);
tupdesc = RelationGetTupleDescriptor(pgindex);
ScanKeyEntryInitialize(&key, 0x0, Anum_pg_index_indrelid,
F_OIDEQ,
ObjectIdGetDatum(relid));
scan = heap_beginscan(pgindex, false, SnapshotNow, 1, &key);
while (HeapTupleIsValid(tuple = heap_getnext(scan, 0)))
{
d = heap_getattr(tuple, Anum_pg_index_indexrelid,
tupdesc, &n);
i++;
if (i % 10 == 0)
ioid = (Oid *) repalloc(ioid, (i + 10) * sizeof(Oid));
ioid[i - 1] = DatumGetObjectId(d);
}
heap_endscan(scan);
heap_close(pgindex);
if (i == 0)
{ /* No one index found */
pfree(ioid);
return;
}
if (Irel != (Relation **) NULL)
*Irel = (Relation *) palloc(i * sizeof(Relation));
for (k = 0; i > 0;)
{
irel = index_open(ioid[--i]);
if (irel != (Relation) NULL)
{
if (Irel != (Relation **) NULL)
(*Irel)[k] = irel;
else
index_close(irel);
k++;
}
else
elog(NOTICE, "CAN't OPEN INDEX %u - SKIP IT", ioid[i]);
}
*nindices = k;
pfree(ioid);
if (Irel != (Relation **) NULL && *nindices == 0)
{
pfree(*Irel);
*Irel = (Relation *) NULL;
}
} /* vc_getindices */
static void
vc_clsindices(int nindices, Relation *Irel)
{
if (Irel == (Relation *) NULL)
return;
while (nindices--)
index_close(Irel[nindices]);
pfree(Irel);
} /* vc_clsindices */
static void
vc_mkindesc(Relation onerel, int nindices, Relation *Irel, IndDesc **Idesc)
{
IndDesc *idcur;
HeapTuple cachetuple;
AttrNumber *attnumP;
int natts;
int i;
*Idesc = (IndDesc *) palloc(nindices * sizeof(IndDesc));
for (i = 0, idcur = *Idesc; i < nindices; i++, idcur++)
{
cachetuple = SearchSysCacheTupleCopy(INDEXRELID,
ObjectIdGetDatum(RelationGetRelid(Irel[i])),
0, 0, 0);
Assert(cachetuple);
/* we never free the copy we make, because Idesc needs it for later */
idcur->tform = (IndexTupleForm) GETSTRUCT(cachetuple);
for (attnumP = &(idcur->tform->indkey[0]), natts = 0;
*attnumP != InvalidAttrNumber && natts != INDEX_MAX_KEYS;
attnumP++, natts++);
if (idcur->tform->indproc != InvalidOid)
{
idcur->finfoP = &(idcur->finfo);
FIgetnArgs(idcur->finfoP) = natts;
natts = 1;
FIgetProcOid(idcur->finfoP) = idcur->tform->indproc;
*(FIgetname(idcur->finfoP)) = '\0';
}
else
idcur->finfoP = (FuncIndexInfo *) NULL;
idcur->natts = natts;
}
} /* vc_mkindesc */
static bool
vc_enough_space(VPageDescr vpd, Size len)
{
len = DOUBLEALIGN(len);
if (len > vpd->vpd_free)
return (false);
if (vpd->vpd_offsets_used < vpd->vpd_offsets_free) /* there are free itemid(s) */
return (true); /* and len <= free_space */
/* ok. noff_usd >= noff_free and so we'll have to allocate new itemid */
if (len <= vpd->vpd_free - sizeof(ItemIdData))
return (true);
return (false);
} /* vc_enough_space */
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