Allow vacuum to perform analyze with shared lock. Update cvs manual.
authorBruce Momjian
Mon, 29 May 2000 15:44:55 +0000 (15:44 +0000)
committerBruce Momjian
Mon, 29 May 2000 15:44:55 +0000 (15:44 +0000)
doc/src/sgml/cvs.sgml
src/backend/commands/vacuum.c
src/include/commands/vacuum.h

index 50f9a0ccbc3031d5cfead4b962b00062be1d1f63..bf2ee60ebc7a2caf54fd77b49d01a4c995e8c830 100644 (file)
@@ -1,5 +1,5 @@
 
@@ -184,7 +184,7 @@ cvs commit
      Do an initial login to the CVS server:
 
      
-$ cvs -d :pserver:[email protected]:/usr/local/cvsroot login
+$ cvs -d :pserver:[email protected]:/home/projects/pgsql/cvsroot login
      
 
      You will be prompted for a password; enter 'postgresql'.
@@ -197,7 +197,7 @@ $ cvs -d :pserver:[email protected]:/usr/local/cvsroot login
     
      Fetch the Postgres sources:
      
-cvs -z3 -d :pserver:[email protected]:/usr/local/cvsroot co -P pgsql
+cvs -z3 -d :pserver:[email protected]:/home/projects/pgsql/cvsroot co -P pgsql
      
 
      which installs the Postgres sources into a 
index 3160e2011080bff04c1f529f1a61837ff82257af..bd8386be3726e8578ff67ef18ec0ceb50f5e4009 100644 (file)
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.151 2000/05/29 01:55:07 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.152 2000/05/29 15:44:55 momjian Exp $
  *
 
  *-------------------------------------------------------------------------
@@ -77,15 +77,17 @@ static void vacuum_shutdown(void);
 static void vac_vacuum(NameData *VacRelP, bool analyze, List *va_cols);
 static VRelList getrels(NameData *VacRelP);
 static void vacuum_rel(Oid relid, bool analyze, List *va_cols);
+static void analyze_rel(Oid relid, List *va_cols);
 static void scan_heap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages);
 static void repair_frag(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages, int nindices, Relation *Irel);
 static void vacuum_heap(VRelStats *vacrelstats, Relation onerel, VPageList vpl);
 static void vacuum_page(Page page, VPageDescr vpd);
 static void vacuum_index(VPageList vpl, Relation indrel, int num_tuples, int keep_tuples);
 static void scan_index(Relation indrel, int num_tuples);
-static void attr_stats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple);
+static void attr_stats(Relation onerel, int attr_cnt, VacAttrStats *vacattrstats, HeapTuple tuple);
 static void bucketcpy(Form_pg_attribute attr, Datum value, Datum *bucket, int *bucket_len);
-static void update_stats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats);
+static void update_relstats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats);
+static void update_attstats(Oid relid, int natts, VacAttrStats *vacattrstats);
 static void del_stats(Oid relid, int attcnt, int *attnums);
 static VPageDescr tid_reaped(ItemPointer itemptr, VPageList vpl);
 static void reap_page(VPageList vpl, VPageDescr vpc);
@@ -100,63 +102,7 @@ static int vac_cmp_offno(const void *left, const void *right);
 static int vac_cmp_vtlinks(const void *left, const void *right);
 static bool enough_space(VPageDescr vpd, Size len);
 static char *show_rusage(struct rusage * ru0);
-
-
-/*
- * This routines handle a special cross-transaction portal.
- * However it is automatically closed in case of abort.
- */
-void
-CommonSpecialPortalOpen(void)
-{
-   char       *pname;
-
-
-   if (CommonSpecialPortalInUse)
-       elog(ERROR, "CommonSpecialPortal is in use");
-
-   /*
-    * Create a portal for safe memory across transactions. 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 = pstrdup(VACPNAME);
-   vac_portal = CreatePortal(pname);
-   pfree(pname);
-
-   /*
-    * Set flag to indicate that vac_portal must be removed after an error.
-    * This global variable is checked in the transaction manager on xact
-    * abort, and the routine CommonSpecialPortalClose() is called if
-    * necessary.
-    */
-   CommonSpecialPortalInUse = true;
-}
-
-void
-CommonSpecialPortalClose(void)
-{
-   /* Clear flag first, to avoid recursion if PortalDrop elog's */
-   CommonSpecialPortalInUse = false;
-
-   /*
-    * Release our portal for cross-transaction memory.
-    */
-   PortalDrop(&vac_portal);
-}
-
-PortalVariableMemory
-CommonSpecialPortalGetMemory(void)
-{
-   return PortalGetVariableMemory(vac_portal);
-}
-
-bool
-CommonSpecialPortalIsOpen(void)
-{
-   return CommonSpecialPortalInUse;
-}
+/* CommonSpecialPortal function at the bottom */
 
 void
 vacuum(char *vacrel, bool verbose, bool analyze, List *va_spec)
@@ -299,6 +245,11 @@ vac_vacuum(NameData *VacRelP, bool analyze, List *va_cols)
    /* vacuum each heap relation */
    for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
        vacuum_rel(cur->vrl_relid, analyze, va_cols);
+
+   /* analyze separately so locking is minimized */
+   if (analyze)
+       for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
+           analyze_rel(cur->vrl_relid, va_cols);
 }
 
 static VRelList
@@ -410,8 +361,7 @@ getrels(NameData *VacRelP)
 static void
 vacuum_rel(Oid relid, bool analyze, List *va_cols)
 {
-   HeapTuple   tuple,
-               typetuple;
+   HeapTuple   tuple;
    Relation    onerel;
    VPageListData vacuum_pages; /* List of pages to vacuum and/or clean
                                 * indices */
@@ -474,125 +424,6 @@ vacuum_rel(Oid relid, bool analyze, List *va_cols)
    vacrelstats->num_pages = vacrelstats->num_tuples = 0;
    vacrelstats->hasindex = false;
 
-   /*
-    * we can VACUUM ANALYZE any table except pg_statistic; see
-    * update_stats
-    */
-   if (analyze &&
-    strcmp(RelationGetRelationName(onerel), StatisticRelationName) != 0)
-   {
-       int         attr_cnt,
-                  *attnums = NULL;
-       Form_pg_attribute *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));
-           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));
-               }
-           }
-           attr_cnt = tcnt;
-       }
-
-       vacrelstats->vacattrstats = (VacAttrStats *) palloc(attr_cnt * sizeof(VacAttrStats));
-
-       for (i = 0; i < attr_cnt; i++)
-       {
-           Operator    func_operator;
-           Form_pg_operator 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 = (Form_pg_operator) 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 = (Form_pg_operator) GETSTRUCT(func_operator);
-               fmgr_info(pgopform->oprcode, &(stats->f_cmplt));
-               stats->op_cmplt = oprid(func_operator);
-           }
-           else
-           {
-               stats->f_cmplt.fn_addr = NULL;
-               stats->op_cmplt = InvalidOid;
-           }
-
-           func_operator = oper(">", stats->attr->atttypid, stats->attr->atttypid, true);
-           if (func_operator != NULL)
-           {
-               pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
-               fmgr_info(pgopform->oprcode, &(stats->f_cmpgt));
-           }
-           else
-               stats->f_cmpgt.fn_addr = NULL;
-
-           typetuple = SearchSysCacheTuple(TYPEOID,
-                                ObjectIdGetDatum(stats->attr->atttypid),
-                                           0, 0, 0);
-           if (HeapTupleIsValid(typetuple))
-           {
-               stats->outfunc = ((Form_pg_type) GETSTRUCT(typetuple))->typoutput;
-               stats->typelem = ((Form_pg_type) GETSTRUCT(typetuple))->typelem;
-           }
-           else
-           {
-               stats->outfunc = InvalidOid;
-               stats->typelem = InvalidOid;
-           }
-       }
-       vacrelstats->va_natts = attr_cnt;
-       /* delete existing pg_statistic rows for relation */
-       del_stats(relid, ((attnums) ? attr_cnt : 0), attnums);
-       if (attnums)
-           pfree(attnums);
-   }
-   else
-   {
-       vacrelstats->va_natts = 0;
-       vacrelstats->vacattrstats = (VacAttrStats *) NULL;
-   }
-
    GetXmaxRecent(&XmaxRecent);
 
    /* scan it */
@@ -631,7 +462,7 @@ vacuum_rel(Oid relid, bool analyze, List *va_cols)
                vacuum_index(&vacuum_pages, Irel[i], vacrelstats->num_tuples, 0);
        }
        else
-/* just scan indices to update statistic */
+       /* just scan indices to update statistic */
        {
            for (i = 0; i < nindices; i++)
                scan_index(Irel[i], vacrelstats->num_tuples);
@@ -662,17 +493,197 @@ vacuum_rel(Oid relid, bool analyze, List *va_cols)
            pfree(fraged_pages.vpl_pagedesc);
    }
 
-   /* update statistics in pg_class */
-   update_stats(vacrelstats->relid, vacrelstats->num_pages,
-           vacrelstats->num_tuples, vacrelstats->hasindex, vacrelstats);
-
    /* all done with this class, but hold lock until commit */
    heap_close(onerel, NoLock);
 
+   /* update statistics in pg_class */
+   update_relstats(vacrelstats->relid, vacrelstats->num_pages,
+           vacrelstats->num_tuples, vacrelstats->hasindex, vacrelstats);
+
    /* next command frees attribute stats */
    CommitTransactionCommand();
 }
 
+/*
+ * analyze_rel() -- analyze relation
+ */
+static void
+analyze_rel(Oid relid, List *va_cols)
+{
+   HeapTuple   tuple,
+               typetuple;
+   Relation    onerel;
+   int32       i;
+   int         attr_cnt,
+              *attnums = NULL;
+   Form_pg_attribute *attr;
+   VacAttrStats *vacattrstats;
+   HeapScanDesc scan;
+
+   StartTransactionCommand();
+
+   /*
+    * Check for user-requested abort.  Note we want this to be inside a
+    * transaction, so xact.c doesn't issue useless NOTICE.
+    */
+   if (QueryCancel)
+       CancelQuery();
+
+   /*
+    * 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);
+   /*
+    * We can VACUUM ANALYZE any table except pg_statistic.
+    * see update_relstats
+    */
+   if (!HeapTupleIsValid(tuple) ||
+       strcmp(NameStr(((Form_pg_class) GETSTRUCT(tuple))->relname),
+               StatisticRelationName) == 0)
+   {
+       CommitTransactionCommand();
+       return;
+   }
+
+   /*
+    * Open the class, get an exclusive lock on it, and check permissions.
+    *
+    * Note we choose to treat permissions failure as a NOTICE and keep
+    * trying to vacuum the rest of the DB --- is this appropriate?
+    */
+   onerel = heap_open(relid, AccessShareLock);
+
+#ifndef NO_SECURITY
+   if (!pg_ownercheck(GetPgUserName(), RelationGetRelationName(onerel),
+                      RELNAME))
+   {
+       /* we already did an elog during vacuum
+       elog(NOTICE, "Skipping \"%s\" --- only table owner can VACUUM it",
+            RelationGetRelationName(onerel));
+       */
+       heap_close(onerel, AccessExclusiveLock);
+       CommitTransactionCommand();
+       return;
+   }
+#endif
+
+   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));
+       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));
+           }
+       }
+       attr_cnt = tcnt;
+   }
+
+   vacattrstats = (VacAttrStats *) palloc(attr_cnt * sizeof(VacAttrStats));
+
+   for (i = 0; i < attr_cnt; i++)
+   {
+       Operator    func_operator;
+       Form_pg_operator pgopform;
+       VacAttrStats *stats;
+
+       stats = &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 = (Form_pg_operator) 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 = (Form_pg_operator) GETSTRUCT(func_operator);
+           fmgr_info(pgopform->oprcode, &(stats->f_cmplt));
+           stats->op_cmplt = oprid(func_operator);
+       }
+       else
+       {
+           stats->f_cmplt.fn_addr = NULL;
+           stats->op_cmplt = InvalidOid;
+       }
+
+       func_operator = oper(">", stats->attr->atttypid, stats->attr->atttypid, true);
+       if (func_operator != NULL)
+       {
+           pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
+           fmgr_info(pgopform->oprcode, &(stats->f_cmpgt));
+       }
+       else
+           stats->f_cmpgt.fn_addr = NULL;
+
+       typetuple = SearchSysCacheTuple(TYPEOID,
+                            ObjectIdGetDatum(stats->attr->atttypid),
+                                       0, 0, 0);
+       if (HeapTupleIsValid(typetuple))
+       {
+           stats->outfunc = ((Form_pg_type) GETSTRUCT(typetuple))->typoutput;
+           stats->typelem = ((Form_pg_type) GETSTRUCT(typetuple))->typelem;
+       }
+       else
+       {
+           stats->outfunc = InvalidOid;
+           stats->typelem = InvalidOid;
+       }
+   }
+   /* delete existing pg_statistic rows for relation */
+   del_stats(relid, ((attnums) ? attr_cnt : 0), attnums);
+
+   scan = heap_beginscan(onerel, false, SnapshotNow, 0, NULL);
+
+   while (HeapTupleIsValid(tuple = heap_getnext(scan, 0)))
+       attr_stats(onerel, attr_cnt, vacattrstats, tuple);
+
+   heap_endscan(scan);
+
+   heap_close(onerel, AccessShareLock);
+
+   /* update statistics in pg_class */
+   update_attstats(relid, attr_cnt, vacattrstats);
+
+   CommitTransactionCommand();
+}
+
 /*
  * scan_heap() -- scan an open heap relation
  *
@@ -979,7 +990,6 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
                    min_tlen = tuple.t_len;
                if (tuple.t_len > max_tlen)
                    max_tlen = tuple.t_len;
-               attr_stats(onerel, vacrelstats, &tuple);
            }
        }
 
@@ -2106,7 +2116,7 @@ scan_index(Relation indrel, int num_tuples)
 
    /* now update statistics in pg_class */
    nipages = RelationGetNumberOfBlocks(indrel);
-   update_stats(RelationGetRelid(indrel), nipages, nitups, false, NULL);
+   update_relstats(RelationGetRelid(indrel), nipages, nitups, false, NULL);
 
    elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u. %s",
         RelationGetRelationName(indrel), nipages, nitups,
@@ -2183,7 +2193,7 @@ vacuum_index(VPageList vpl, Relation indrel, int num_tuples, int keep_tuples)
 
    /* now update statistics in pg_class */
    num_pages = RelationGetNumberOfBlocks(indrel);
-   update_stats(RelationGetRelid(indrel), num_pages, num_index_tuples, false, NULL);
+   update_relstats(RelationGetRelid(indrel), num_pages, num_index_tuples, false, NULL);
 
    elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u: Deleted %u. %s",
         RelationGetRelationName(indrel), num_pages,
@@ -2263,11 +2273,9 @@ tid_reaped(ItemPointer itemptr, VPageList vpl)
  *
  */
 static void
-attr_stats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple)
+attr_stats(Relation onerel, int attr_cnt, VacAttrStats *vacattrstats, HeapTuple tuple)
 {
-   int         i,
-               attr_cnt = vacrelstats->va_natts;
-   VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
+   int         i;
    TupleDesc   tupDesc = onerel->rd_att;
    Datum       value;
    bool        isnull;
@@ -2387,7 +2395,7 @@ bucketcpy(Form_pg_attribute attr, Datum value, Datum *bucket, int *bucket_len)
 }
 
 /*
- * update_stats() -- update statistics for one relation
+ * update_relstats() -- update statistics for one relation
  *
  *     Statistics are stored in several places: the pg_class row for the
  *     relation has stats about the whole relation, the pg_attribute rows
@@ -2408,29 +2416,15 @@ bucketcpy(Form_pg_attribute attr, Datum value, Datum *bucket, int *bucket_len)
  *     Updating pg_class's own statistics would be especially tricky.
  *     Of course, this only works for fixed-size never-null columns, but
  *     these are.
- *
- *     Updates of pg_attribute statistics are handled in the same way
- *     for the same reasons.
- *
- *     To keep things simple, we punt for pg_statistic, and don't try
- *     to compute or store rows for pg_statistic itself in pg_statistic.
- *     This could possibly be made to work, but it's not worth the trouble.
  */
 static void
-update_stats(Oid relid, int num_pages, int num_tuples, bool hasindex,
+update_relstats(Oid relid, int num_pages, int num_tuples, bool hasindex,
            VRelStats *vacrelstats)
 {
-   Relation    rd,
-               ad,
-               sd;
-   HeapScanDesc scan;
+   Relation    rd;
    HeapTupleData rtup;
-   HeapTuple   ctup,
-               atup,
-               stup;
+   HeapTuple   ctup;
    Form_pg_class pgcform;
-   ScanKeyData askey;
-   Form_pg_attribute attp;
    Buffer      buffer;
 
    /*
@@ -2461,202 +2455,217 @@ update_stats(Oid relid, int num_pages, int num_tuples, bool hasindex,
    WriteBuffer(buffer);
 
    heap_close(rd, RowExclusiveLock);
+}
 
-   if (vacrelstats != NULL && vacrelstats->va_natts > 0)
-   {
-       VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
-       int         natts = vacrelstats->va_natts;
+/*
+ * update_attstats() -- update attribute statistics for one relation
+ *
+ *     Updates of pg_attribute statistics are handled by over-write.
+ *     for reasons described above.
+ *
+ *     To keep things simple, we punt for pg_statistic, and don't try
+ *     to compute or store rows for pg_statistic itself in pg_statistic.
+ *     This could possibly be made to work, but it's not worth the trouble.
+ */
+static void
+update_attstats(Oid relid, int natts, VacAttrStats *vacattrstats)
+{
+   Relation    ad,
+               sd;
+   HeapScanDesc scan;
+   HeapTuple   atup,
+               stup;
+   ScanKeyData askey;
+   Form_pg_attribute attp;
 
-       ad = heap_openr(AttributeRelationName, RowExclusiveLock);
-       sd = heap_openr(StatisticRelationName, RowExclusiveLock);
+   ad = heap_openr(AttributeRelationName, RowExclusiveLock);
+   sd = heap_openr(StatisticRelationName, RowExclusiveLock);
 
-       /* Find pg_attribute rows for this relation */
-       ScanKeyEntryInitialize(&askey, 0, Anum_pg_attribute_attrelid,
-                              F_INT4EQ, relid);
+   /* Find pg_attribute rows for this relation */
+   ScanKeyEntryInitialize(&askey, 0, Anum_pg_attribute_attrelid,
+                          F_INT4EQ, relid);
 
-       scan = heap_beginscan(ad, false, SnapshotNow, 1, &askey);
+   scan = heap_beginscan(ad, false, SnapshotNow, 1, &askey);
 
-       while (HeapTupleIsValid(atup = heap_getnext(scan, 0)))
+   while (HeapTupleIsValid(atup = heap_getnext(scan, 0)))
+   {
+       int         i;
+       VacAttrStats *stats;
+
+       attp = (Form_pg_attribute) GETSTRUCT(atup);
+       if (attp->attnum <= 0)      /* skip system attributes for now */
+           continue;
+
+       for (i = 0; i < natts; i++)
        {
-           int         i;
-           VacAttrStats *stats;
+           if (attp->attnum == vacattrstats[i].attr->attnum)
+               break;
+       }
+       if (i >= natts)
+           continue;       /* skip attr if no stats collected */
+       stats = &(vacattrstats[i]);
 
-           attp = (Form_pg_attribute) GETSTRUCT(atup);
-           if (attp->attnum <= 0)      /* skip system attributes for now */
-               continue;
+       if (VacAttrStatsEqValid(stats))
+       {
+           float32data selratio;   /* average ratio of rows selected
+                                    * for a random constant */
 
-           for (i = 0; i < natts; i++)
+           /* Compute disbursion */
+           if (stats->nonnull_cnt == 0 && stats->null_cnt == 0)
            {
-               if (attp->attnum == vacattrstats[i].attr->attnum)
-                   break;
-           }
-           if (i >= natts)
-               continue;       /* skip attr if no stats collected */
-           stats = &(vacattrstats[i]);
 
-           if (VacAttrStatsEqValid(stats))
+               /*
+                * empty relation, so put a dummy value in
+                * attdisbursion
+                */
+               selratio = 0;
+           }
+           else if (stats->null_cnt <= 1 && stats->best_cnt == 1)
            {
-               float32data selratio;   /* average ratio of rows selected
-                                        * for a random constant */
-
-               /* Compute disbursion */
-               if (stats->nonnull_cnt == 0 && stats->null_cnt == 0)
+               /*
+                * looks like we have a unique-key attribute --- flag
+                * this with special -1.0 flag value.
+                *
+                * The correct disbursion is 1.0/numberOfRows, but since
+                * the relation row count can get updated without
+                * recomputing disbursion, we want to store a
+                * "symbolic" value and figure 1.0/numberOfRows on the
+                * fly.
+                */
+               selratio = -1;
+           }
+           else
+           {
+               if (VacAttrStatsLtGtValid(stats) &&
+               stats->min_cnt + stats->max_cnt == stats->nonnull_cnt)
                {
 
                    /*
-                    * empty relation, so put a dummy value in
-                    * attdisbursion
+                    * exact result when there are just 1 or 2
+                    * values...
                     */
-                   selratio = 0;
-               }
-               else if (stats->null_cnt <= 1 && stats->best_cnt == 1)
-               {
+                   double      min_cnt_d = stats->min_cnt,
+                               max_cnt_d = stats->max_cnt,
+                               null_cnt_d = stats->null_cnt;
+                   double      total = ((double) stats->nonnull_cnt) + null_cnt_d;
 
-                   /*
-                    * looks like we have a unique-key attribute --- flag
-                    * this with special -1.0 flag value.
-                    *
-                    * The correct disbursion is 1.0/numberOfRows, but since
-                    * the relation row count can get updated without
-                    * recomputing disbursion, we want to store a
-                    * "symbolic" value and figure 1.0/numberOfRows on the
-                    * fly.
-                    */
-                   selratio = -1;
+                   selratio = (min_cnt_d * min_cnt_d + max_cnt_d * max_cnt_d + null_cnt_d * null_cnt_d) / (total * total);
                }
                else
                {
-                   if (VacAttrStatsLtGtValid(stats) &&
-                   stats->min_cnt + stats->max_cnt == stats->nonnull_cnt)
-                   {
-
-                       /*
-                        * exact result when there are just 1 or 2
-                        * values...
-                        */
-                       double      min_cnt_d = stats->min_cnt,
-                                   max_cnt_d = stats->max_cnt,
-                                   null_cnt_d = stats->null_cnt;
-                       double      total = ((double) stats->nonnull_cnt) + null_cnt_d;
-
-                       selratio = (min_cnt_d * min_cnt_d + max_cnt_d * max_cnt_d + null_cnt_d * null_cnt_d) / (total * total);
-                   }
-                   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);
+                   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);
-                   }
-                   /* Make sure calculated values are in-range */
-                   if (selratio < 0.0)
-                       selratio = 0.0;
-                   else if (selratio > 1.0)
-                       selratio = 1.0;
+                   /*
+                    * we assume count of other values are 20% of best
+                    * count in table
+                    */
+                   selratio = (most * most + 0.20 * most * (total - most)) / (total * total);
                }
+               /* Make sure calculated values are in-range */
+               if (selratio < 0.0)
+                   selratio = 0.0;
+               else if (selratio > 1.0)
+                   selratio = 1.0;
+           }
 
-               /* overwrite the existing statistics in the tuple */
-               attp->attdisbursion = selratio;
+           /* overwrite the existing statistics in the tuple */
+           attp->attdisbursion = selratio;
 
-               /* invalidate the tuple in the cache and write the buffer */
-               RelationInvalidateHeapTuple(ad, atup);
-               WriteNoReleaseBuffer(scan->rs_cbuf);
+           /* invalidate the tuple in the cache and write the buffer */
+           RelationInvalidateHeapTuple(ad, atup);
+           WriteNoReleaseBuffer(scan->rs_cbuf);
 
-               /*
-                * Create pg_statistic tuples for the relation, if we have
-                * gathered the right data.  del_stats() previously
-                * deleted all the pg_statistic tuples for the rel, so we
-                * just have to insert new ones here.
+           /*
+            * Create pg_statistic tuples for the relation, if we have
+            * gathered the right data.  del_stats() previously
+            * deleted all the pg_statistic tuples for the rel, so we
+            * just have to insert new ones here.
+            *
+            * Note vacuum_rel() has seen to it that we won't come here
+            * when vacuuming pg_statistic itself.
+            */
+           if (VacAttrStatsLtGtValid(stats) && stats->initialized)
+           {
+               float32data nullratio;
+               float32data bestratio;
+               FmgrInfo    out_function;
+               char       *out_string;
+               double      best_cnt_d = stats->best_cnt,
+                           null_cnt_d = stats->null_cnt,
+                           nonnull_cnt_d = stats->nonnull_cnt;     /* prevent overflow */
+               Datum       values[Natts_pg_statistic];
+               char        nulls[Natts_pg_statistic];
+
+               nullratio = null_cnt_d / (nonnull_cnt_d + null_cnt_d);
+               bestratio = best_cnt_d / (nonnull_cnt_d + null_cnt_d);
+
+               fmgr_info(stats->outfunc, &out_function);
+
+               for (i = 0; i < Natts_pg_statistic; ++i)
+                   nulls[i] = ' ';
+
+               /* ----------------
+                *  initialize values[]
+                * ----------------
+                */
+               i = 0;
+               values[i++] = (Datum) relid;        /* starelid */
+               values[i++] = (Datum) attp->attnum; /* staattnum */
+               values[i++] = (Datum) stats->op_cmplt;      /* staop */
+               /* hack: this code knows float4 is pass-by-ref */
+               values[i++] = PointerGetDatum(&nullratio);  /* stanullfrac */
+               values[i++] = PointerGetDatum(&bestratio);  /* stacommonfrac */
+               out_string = (*fmgr_faddr(&out_function)) (stats->best, stats->typelem, stats->attr->atttypmod);
+               values[i++] = PointerGetDatum(textin(out_string));  /* stacommonval */
+               pfree(out_string);
+               out_string = (*fmgr_faddr(&out_function)) (stats->min, stats->typelem, stats->attr->atttypmod);
+               values[i++] = PointerGetDatum(textin(out_string));  /* staloval */
+               pfree(out_string);
+               out_string = (char *) (*fmgr_faddr(&out_function)) (stats->max, stats->typelem, stats->attr->atttypmod);
+               values[i++] = PointerGetDatum(textin(out_string));  /* stahival */
+               pfree(out_string);
+
+               stup = heap_formtuple(sd->rd_att, values, nulls);
+
+               /* ----------------
+                *  Watch out for oversize tuple, which can happen if
+                *  all three of the saved data values are long.
+                *  Our fallback strategy is just to not store the
+                *  pg_statistic tuple at all in that case.  (We could
+                *  replace the values by NULLs and still store the
+                *  numeric stats, but presently selfuncs.c couldn't
+                *  do anything useful with that case anyway.)
                 *
-                * Note vacuum_rel() has seen to it that we won't come here
-                * when vacuuming pg_statistic itself.
+                *  We could reduce the probability of overflow, but not
+                *  prevent it, by storing the data values as compressed
+                *  text; is that worth doing?  The problem should go
+                *  away whenever long tuples get implemented...
+                * ----------------
                 */
-               if (VacAttrStatsLtGtValid(stats) && stats->initialized)
+               if (MAXALIGN(stup->t_len) <= MaxTupleSize)
                {
-                   float32data nullratio;
-                   float32data bestratio;
-                   FmgrInfo    out_function;
-                   char       *out_string;
-                   double      best_cnt_d = stats->best_cnt,
-                               null_cnt_d = stats->null_cnt,
-                               nonnull_cnt_d = stats->nonnull_cnt;     /* prevent overflow */
-                   Datum       values[Natts_pg_statistic];
-                   char        nulls[Natts_pg_statistic];
-
-                   nullratio = null_cnt_d / (nonnull_cnt_d + null_cnt_d);
-                   bestratio = best_cnt_d / (nonnull_cnt_d + null_cnt_d);
-
-                   fmgr_info(stats->outfunc, &out_function);
-
-                   for (i = 0; i < Natts_pg_statistic; ++i)
-                       nulls[i] = ' ';
-
-                   /* ----------------
-                    *  initialize values[]
-                    * ----------------
-                    */
-                   i = 0;
-                   values[i++] = (Datum) relid;        /* starelid */
-                   values[i++] = (Datum) attp->attnum; /* staattnum */
-                   values[i++] = (Datum) stats->op_cmplt;      /* staop */
-                   /* hack: this code knows float4 is pass-by-ref */
-                   values[i++] = PointerGetDatum(&nullratio);  /* stanullfrac */
-                   values[i++] = PointerGetDatum(&bestratio);  /* stacommonfrac */
-                   out_string = (*fmgr_faddr(&out_function)) (stats->best, stats->typelem, stats->attr->atttypmod);
-                   values[i++] = PointerGetDatum(textin(out_string));  /* stacommonval */
-                   pfree(out_string);
-                   out_string = (*fmgr_faddr(&out_function)) (stats->min, stats->typelem, stats->attr->atttypmod);
-                   values[i++] = PointerGetDatum(textin(out_string));  /* staloval */
-                   pfree(out_string);
-                   out_string = (char *) (*fmgr_faddr(&out_function)) (stats->max, stats->typelem, stats->attr->atttypmod);
-                   values[i++] = PointerGetDatum(textin(out_string));  /* stahival */
-                   pfree(out_string);
-
-                   stup = heap_formtuple(sd->rd_att, values, nulls);
-
-                   /* ----------------
-                    *  Watch out for oversize tuple, which can happen if
-                    *  all three of the saved data values are long.
-                    *  Our fallback strategy is just to not store the
-                    *  pg_statistic tuple at all in that case.  (We could
-                    *  replace the values by NULLs and still store the
-                    *  numeric stats, but presently selfuncs.c couldn't
-                    *  do anything useful with that case anyway.)
-                    *
-                    *  We could reduce the probability of overflow, but not
-                    *  prevent it, by storing the data values as compressed
-                    *  text; is that worth doing?  The problem should go
-                    *  away whenever long tuples get implemented...
-                    * ----------------
-                    */
-                   if (MAXALIGN(stup->t_len) <= MaxTupleSize)
-                   {
-                       /* OK, store tuple and update indexes too */
-                       Relation    irelations[Num_pg_statistic_indices];
+                   /* OK, store tuple and update indexes too */
+                   Relation    irelations[Num_pg_statistic_indices];
 
-                       heap_insert(sd, stup);
-                       CatalogOpenIndices(Num_pg_statistic_indices, Name_pg_statistic_indices, irelations);
-                       CatalogIndexInsert(irelations, Num_pg_statistic_indices, sd, stup);
-                       CatalogCloseIndices(Num_pg_statistic_indices, irelations);
-                   }
-
-                   /* release allocated space */
-                   pfree(DatumGetPointer(values[Anum_pg_statistic_stacommonval - 1]));
-                   pfree(DatumGetPointer(values[Anum_pg_statistic_staloval - 1]));
-                   pfree(DatumGetPointer(values[Anum_pg_statistic_stahival - 1]));
-                   heap_freetuple(stup);
+                   heap_insert(sd, stup);
+                   CatalogOpenIndices(Num_pg_statistic_indices, Name_pg_statistic_indices, irelations);
+                   CatalogIndexInsert(irelations, Num_pg_statistic_indices, sd, stup);
+                   CatalogCloseIndices(Num_pg_statistic_indices, irelations);
                }
+
+               /* release allocated space */
+               pfree(DatumGetPointer(values[Anum_pg_statistic_stacommonval - 1]));
+               pfree(DatumGetPointer(values[Anum_pg_statistic_staloval - 1]));
+               pfree(DatumGetPointer(values[Anum_pg_statistic_stahival - 1]));
+               heap_freetuple(stup);
            }
        }
-       heap_endscan(scan);
-       /* close rels, but hold locks till upcoming commit */
-       heap_close(ad, NoLock);
-       heap_close(sd, NoLock);
    }
+   heap_endscan(scan);
+   /* close rels, but hold locks till upcoming commit */
+   heap_close(ad, NoLock);
+   heap_close(sd, NoLock);
 }
 
 /*
@@ -2867,6 +2876,62 @@ vac_cmp_vtlinks(const void *left, const void *right)
 
 }
 
+/*
+ * This routines handle a special cross-transaction portal.
+ * However it is automatically closed in case of abort.
+ */
+void
+CommonSpecialPortalOpen(void)
+{
+   char       *pname;
+
+
+   if (CommonSpecialPortalInUse)
+       elog(ERROR, "CommonSpecialPortal is in use");
+
+   /*
+    * Create a portal for safe memory across transactions. 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 = pstrdup(VACPNAME);
+   vac_portal = CreatePortal(pname);
+   pfree(pname);
+
+   /*
+    * Set flag to indicate that vac_portal must be removed after an error.
+    * This global variable is checked in the transaction manager on xact
+    * abort, and the routine CommonSpecialPortalClose() is called if
+    * necessary.
+    */
+   CommonSpecialPortalInUse = true;
+}
+
+void
+CommonSpecialPortalClose(void)
+{
+   /* Clear flag first, to avoid recursion if PortalDrop elog's */
+   CommonSpecialPortalInUse = false;
+
+   /*
+    * Release our portal for cross-transaction memory.
+    */
+   PortalDrop(&vac_portal);
+}
+
+PortalVariableMemory
+CommonSpecialPortalGetMemory(void)
+{
+   return PortalGetVariableMemory(vac_portal);
+}
+
+bool
+CommonSpecialPortalIsOpen(void)
+{
+   return CommonSpecialPortalInUse;
+}
+
 static void
 get_indices(Oid relid, int *nindices, Relation **Irel)
 {
index 136721c4e17d9657e82b69a34093ed0e2883683b..afdd0a9e6b90fd36bc10ba9da5a1c0bae85d5955 100644 (file)
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: vacuum.h,v 1.27 2000/04/12 17:16:32 momjian Exp $
+ * $Id: vacuum.h,v 1.28 2000/05/29 15:44:55 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -125,8 +125,6 @@ typedef struct VRelStats
    Size        min_tlen;
    Size        max_tlen;
    bool        hasindex;
-   int         va_natts;       /* number of attrs being analyzed */
-   VacAttrStats *vacattrstats;
    int         num_vtlinks;
    VTupleLink  vtlinks;
 } VRelStats;