granicus.if.org Git - postgresql/blob - src/include/utils/catcache.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * catcache.h--
   4  *        Low-level catalog cache definitions.
   5  *
   6  *
   7  * Copyright (c) 1994, Regents of the University of California
   8  *
   9  * $Id: catcache.h,v 1.6 1997/09/07 05:02:14 momjian Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef CATCACHE_H
  14 #define CATCACHE_H
  15
  16 /* #define              CACHEDEBUG               turns DEBUG elogs on */
  17
  18 #include <access/htup.h>
  19 #include <lib/dllist.h>
  20 #include <nodes/memnodes.h>
  21 #include <utils/rel.h>
  22
  23 /*
  24  *              struct catctup:                 tuples in the cache.
  25  *              struct catcache:                information for managing a cache.
  26  */
  27
  28 typedef struct catctup
  29 {
  30         HeapTuple               ct_tup;         /* A pointer to a tuple                 */
  31         Dlelem             *ct_node;    /* points to LRU list is the CatCTup is in
  32                                                                  * the cache, else, points to the cache if
  33                                                                  * the CatCTup is in LRU list */
  34 }                               CatCTup;
  35
  36 /* voodoo constants */
  37 #define NCCBUCK 500                             /* CatCache buckets */
  38 #define MAXTUP 300                              /* Maximum # of tuples cached per cache */
  39
  40 typedef struct catcache
  41 {
  42         Oid                             relationId;
  43         Oid                             indexId;
  44         char               *cc_relname; /* relation name for defered open */
  45         char               *cc_indname; /* index name for defered open */
  46                                         HeapTuple(*cc_iscanfunc) ();            /* index scanfunction */
  47         TupleDesc               cc_tupdesc; /* tuple descriptor from reldesc */
  48         int                             id;                     /* XXX could be improved -hirohama */
  49         short                   cc_ntup;        /* # of tuples in this cache    */
  50         short                   cc_maxtup;      /* max # of tuples allowed (LRU) */
  51         short                   cc_nkeys;
  52         short                   cc_size;
  53         short                   cc_key[4];
  54         short                   cc_klen[4];
  55         ScanKeyData             cc_skey[4];
  56         struct catcache *cc_next;
  57         Dllist             *cc_lrulist; /* LRU list, most recent first */
  58         Dllist             *cc_cache[NCCBUCK + 1];
  59 }                               CatCache;
  60
  61 #define InvalidCatalogCacheId   (-1)
  62
  63 extern struct catcache *Caches;
  64 extern GlobalMemory CacheCxt;
  65
  66 extern void
  67 CatalogCacheIdInvalidate(int cacheId, Index hashIndex,
  68                                                  ItemPointer pointer);
  69 extern void             ResetSystemCache(void);
  70 extern CatCache *
  71 InitSysCache(char *relname, char *indname, int id, int nkeys,
  72                          int key[], HeapTuple(*iScanfuncP) ());
  73 extern HeapTuple
  74 SearchSysCache(struct catcache * cache, Datum v1, Datum v2,
  75                            Datum v3, Datum v4);
  76 extern void
  77 RelationInvalidateCatalogCacheTuple(Relation relation,
  78                                                                         HeapTuple tuple, void (*function) ());
  79
  80 #endif                                                  /* CATCACHE_H */