/Users/deen/code/yugabyte-db/src/postgres/src/include/utils/catcache.h

Source
/*-------------------------------------------------------------------------
 *
 * catcache.h
 *    Low-level catalog cache definitions.
 *
 * NOTE: every catalog cache must have a corresponding unique index on
 * the system table that it caches --- ie, the index must match the keys
 * used to do lookups in this cache.  All cache fetches are done with
 * indexscans (under normal conditions).  The index should be unique to
 * guarantee that there can only be one matching row for a key combination.
 *
 *
 * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/utils/catcache.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef CATCACHE_H
#define CATCACHE_H

#include "access/htup.h"
#include "access/skey.h"
#include "lib/ilist.h"
#include "utils/relcache.h"

/*
 *    struct catctup:     individual tuple in the cache.
 *    struct catclist:    list of tuples matching a partial key.
 *    struct catcache:    information for managing a cache.
 *    struct catcacheheader:  information for managing all the caches.
 */

#define CATCACHE_MAXKEYS    4


/* function computing a datum's hash */
typedef uint32 (*CCHashFN) (Datum datum);

/* function computing equality of two datums */
typedef bool (*CCFastEqualFN) (Datum a, Datum b);

typedef struct catcache
{
  int     id;       /* cache identifier --- see syscache.h */
  int     cc_nbuckets;  /* # of hash buckets in this cache */
  TupleDesc cc_tupdesc;   /* tuple descriptor (copied from reldesc) */
  dlist_head *cc_bucket;    /* hash buckets */
  CCHashFN  cc_hashfunc[CATCACHE_MAXKEYS];  /* hash function for each key */
  CCFastEqualFN cc_fastequal[CATCACHE_MAXKEYS]; /* fast equal function for
                           * each key */
  int     cc_keyno[CATCACHE_MAXKEYS]; /* AttrNumber of each key */
  dlist_head  cc_lists;   /* list of CatCList structs */
  int     cc_ntup;    /* # of tuples currently in this cache */
  int     cc_nkeys;   /* # of keys (1..CATCACHE_MAXKEYS) */
  const char *cc_relname;   /* name of relation the tuples come from */
  Oid     cc_reloid;    /* OID of relation the tuples come from */
  Oid     cc_indexoid;  /* OID of index matching cache keys */
  bool    cc_relisshared; /* is relation shared across databases? */
  slist_node  cc_next;    /* list link */
  ScanKeyData cc_skey[CATCACHE_MAXKEYS];  /* precomputed key info for heap
                       * scans */

  /*
   * Keep these at the end, so that compiling catcache.c with CATCACHE_STATS
   * doesn't break ABI for other modules
   */
#ifdef CATCACHE_STATS
  long    cc_searches;  /* total # searches against this cache */
  long    cc_hits;    /* # of matches against existing entry */
  long    cc_neg_hits;  /* # of matches against negative entry */
  long    cc_newloads;  /* # of successful loads of new entry */

  /*
   * cc_searches - (cc_hits + cc_neg_hits + cc_newloads) is number of failed
   * searches, each of which will result in loading a negative entry
   */
  long    cc_invals;    /* # of entries invalidated from cache */
  long    cc_lsearches; /* total # list-searches */
  long    cc_lhits;   /* # of matches against existing lists */
#endif
} CatCache;


typedef struct catctup
{
  int     ct_magic;   /* for identifying CatCTup entries */
#define CT_MAGIC   0x57261502

  uint32    hash_value;   /* hash value for this tuple's keys */

  /*
   * Lookup keys for the entry. By-reference datums point into the tuple for
   * positive cache entries, and are separately allocated for negative ones.
   */
  Datum   keys[CATCACHE_MAXKEYS];

  /*
   * Each tuple in a cache is a member of a dlist that stores the elements
   * of its hash bucket.  We keep each dlist in LRU order to speed repeated
   * lookups.
   */
  dlist_node  cache_elem;   /* list member of per-bucket list */

  /*
   * A tuple marked "dead" must not be returned by subsequent searches.
   * However, it won't be physically deleted from the cache until its
   * refcount goes to zero.  (If it's a member of a CatCList, the list's
   * refcount must go to zero, too; also, remember to mark the list dead at
   * the same time the tuple is marked.)
   *
   * A negative cache entry is an assertion that there is no tuple matching
   * a particular key.  This is just as useful as a normal entry so far as
   * avoiding catalog searches is concerned.  Management of positive and
   * negative entries is identical.
   */
  int     refcount;   /* number of active references */
  bool    dead;     /* dead but not yet removed? */
  bool    negative;   /* negative cache entry? */
  HeapTupleData tuple;    /* tuple management header */

  /*
   * The tuple may also be a member of at most one CatCList.  (If a single
   * catcache is list-searched with varying numbers of keys, we may have to
   * make multiple entries for the same tuple because of this restriction.
   * Currently, that's not expected to be common, so we accept the potential
   * inefficiency.)
   */
  struct catclist *c_list;  /* containing CatCList, or NULL if none */

  CatCache   *my_cache;   /* link to owning catcache */
  /* properly aligned tuple data follows, unless a negative entry */
} CatCTup;


/*
 * A CatCList describes the result of a partial search, ie, a search using
 * only the first K key columns of an N-key cache.  We store the keys used
 * into the keys attribute to represent the stored key set.  The CatCList
 * object contains links to cache entries for all the table rows satisfying
 * the partial key.  (Note: none of these will be negative cache entries.)
 *
 * A CatCList is only a member of a per-cache list; we do not currently
 * divide them into hash buckets.
 *
 * A list marked "dead" must not be returned by subsequent searches.
 * However, it won't be physically deleted from the cache until its
 * refcount goes to zero.  (A list should be marked dead if any of its
 * member entries are dead.)
 *
 * If "ordered" is true then the member tuples appear in the order of the
 * cache's underlying index.  This will be true in normal operation, but
 * might not be true during bootstrap or recovery operations. (namespace.c
 * is able to save some cycles when it is true.)
 */
typedef struct catclist
{
  int     cl_magic;   /* for identifying CatCList entries */
#define CL_MAGIC   0x52765103

  uint32    hash_value;   /* hash value for lookup keys */

  dlist_node  cache_elem;   /* list member of per-catcache list */

  /*
   * Lookup keys for the entry, with the first nkeys elements being valid.
   * All by-reference are separately allocated.
   */
  Datum   keys[CATCACHE_MAXKEYS];

  int     refcount;   /* number of active references */
  bool    dead;     /* dead but not yet removed? */
  bool    ordered;    /* members listed in index order? */
  short   nkeys;      /* number of lookup keys specified */
  int     n_members;    /* number of member tuples */
  CatCache   *my_cache;   /* link to owning catcache */
  CatCTup    *members[FLEXIBLE_ARRAY_MEMBER]; /* members */
} CatCList;


typedef struct catcacheheader
{
  slist_head  ch_caches;    /* head of list of CatCache structs */
  int     ch_ntup;    /* # of tuples in all caches */
} CatCacheHeader;


/* this extern duplicates utils/memutils.h... */
extern PGDLLIMPORT MemoryContext CacheMemoryContext;

extern void CreateCacheMemoryContext(void);

extern CatCache *InitCatCache(int id, Oid reloid, Oid indexoid,
       int nkeys, const int *key,
       int nbuckets);

extern void InitCatCachePhase2(CatCache *cache, bool touch_index);

extern HeapTuple SearchCatCache(CatCache *cache,
         Datum v1, Datum v2, Datum v3, Datum v4);
extern HeapTuple SearchCatCache1(CatCache *cache,
        Datum v1);
extern HeapTuple SearchCatCache2(CatCache *cache,
        Datum v1, Datum v2);
extern HeapTuple SearchCatCache3(CatCache *cache,
        Datum v1, Datum v2, Datum v3);
extern HeapTuple SearchCatCache4(CatCache *cache,
        Datum v1, Datum v2, Datum v3, Datum v4);
extern void ReleaseCatCache(HeapTuple tuple);

extern uint32 GetCatCacheHashValue(CatCache *cache,
           Datum v1, Datum v2,
           Datum v3, Datum v4);

/* Used in IsYugaByteEnabled() mode only */
extern void SetCatCacheTuple(CatCache *cache, HeapTuple tup, TupleDesc tupdesc);
extern void SetCatCacheList(CatCache *cache, int nkeys, List *fnlist);

extern CatCList *SearchCatCacheList(CatCache *cache, int nkeys,
           Datum v1, Datum v2,
           Datum v3);
extern void ReleaseCatCacheList(CatCList *list);

extern void ResetCatalogCaches(void);
extern void CatalogCacheFlushCatalog(Oid catId);
extern void CatCacheInvalidate(CatCache *cache, uint32 hashValue);
extern void PrepareToInvalidateCacheTuple(Relation relation,
                HeapTuple tuple,
                HeapTuple newtuple,
                void (*function) (int, uint32, Oid));
extern bool RelationHasCachedLists(Relation relation);

extern void PrintCatCacheLeakWarning(HeapTuple tuple);
extern void PrintCatCacheListLeakWarning(CatCList *list);

extern long GetCatCacheMisses();

#endif              /* CATCACHE_H */

YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

Coverage Report

Created: 2022-03-22 16:43

Line	Count	Source
1		/*-------------------------------------------------------------------------
2		*
3		* catcache.h
4		* Low-level catalog cache definitions.
5		*
6		* NOTE: every catalog cache must have a corresponding unique index on
7		* the system table that it caches --- ie, the index must match the keys
8		* used to do lookups in this cache. All cache fetches are done with
9		* indexscans (under normal conditions). The index should be unique to
10		* guarantee that there can only be one matching row for a key combination.
11		*
12		*
13		* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
14		* Portions Copyright (c) 1994, Regents of the University of California
15		*
16		* src/include/utils/catcache.h
17		*
18		*-------------------------------------------------------------------------
19		*/
20		#ifndef CATCACHE_H
21		#define CATCACHE_H
22
23		#include "access/htup.h"
24		#include "access/skey.h"
25		#include "lib/ilist.h"
26		#include "utils/relcache.h"
27
28		/*
29		* struct catctup: individual tuple in the cache.
30		* struct catclist: list of tuples matching a partial key.
31		* struct catcache: information for managing a cache.
32		* struct catcacheheader: information for managing all the caches.
33		*/
34
35	154M	#define CATCACHE_MAXKEYS 4
36
37
38		/* function computing a datum's hash */
39		typedef uint32 (*CCHashFN) (Datum datum);
40
41		/* function computing equality of two datums */
42		typedef bool (*CCFastEqualFN) (Datum a, Datum b);
43
44		typedef struct catcache
45		{
46		int id; /* cache identifier --- see syscache.h */
47		int cc_nbuckets; /* # of hash buckets in this cache */
48		TupleDesc cc_tupdesc; /* tuple descriptor (copied from reldesc) */
49		dlist_head cc_bucket; / hash buckets */
50		CCHashFN cc_hashfunc[CATCACHE_MAXKEYS]; /* hash function for each key */
51		CCFastEqualFN cc_fastequal[CATCACHE_MAXKEYS]; /* fast equal function for
52		* each key */
53		int cc_keyno[CATCACHE_MAXKEYS]; /* AttrNumber of each key */
54		dlist_head cc_lists; /* list of CatCList structs */
55		int cc_ntup; /* # of tuples currently in this cache */
56		int cc_nkeys; /* # of keys (1..CATCACHE_MAXKEYS) */
57		const char cc_relname; / name of relation the tuples come from */
58		Oid cc_reloid; /* OID of relation the tuples come from */
59		Oid cc_indexoid; /* OID of index matching cache keys */
60		bool cc_relisshared; /* is relation shared across databases? */
61		slist_node cc_next; /* list link */
62		ScanKeyData cc_skey[CATCACHE_MAXKEYS]; /* precomputed key info for heap
63		* scans */
64
65		/*
66		* Keep these at the end, so that compiling catcache.c with CATCACHE_STATS
67		* doesn't break ABI for other modules
68		*/
69		#ifdef CATCACHE_STATS
70		long cc_searches; /* total # searches against this cache */
71		long cc_hits; /* # of matches against existing entry */
72		long cc_neg_hits; /* # of matches against negative entry */
73		long cc_newloads; /* # of successful loads of new entry */
74
75		/*
76		* cc_searches - (cc_hits + cc_neg_hits + cc_newloads) is number of failed
77		* searches, each of which will result in loading a negative entry
78		*/
79		long cc_invals; /* # of entries invalidated from cache */
80		long cc_lsearches; /* total # list-searches */
81		long cc_lhits; /* # of matches against existing lists */
82		#endif
83		} CatCache;
84
85
86		typedef struct catctup
87		{
88		int ct_magic; /* for identifying CatCTup entries */
89	31.9M	#define CT_MAGIC 0x57261502
90
91		uint32 hash_value; /* hash value for this tuple's keys */
92
93		/*
94		* Lookup keys for the entry. By-reference datums point into the tuple for
95		* positive cache entries, and are separately allocated for negative ones.
96		*/
97		Datum keys[CATCACHE_MAXKEYS];
98
99		/*
100		* Each tuple in a cache is a member of a dlist that stores the elements
101		* of its hash bucket. We keep each dlist in LRU order to speed repeated
102		* lookups.
103		*/
104		dlist_node cache_elem; /* list member of per-bucket list */
105
106		/*
107		* A tuple marked "dead" must not be returned by subsequent searches.
108		* However, it won't be physically deleted from the cache until its
109		* refcount goes to zero. (If it's a member of a CatCList, the list's
110		* refcount must go to zero, too; also, remember to mark the list dead at
111		* the same time the tuple is marked.)
112		*
113		* A negative cache entry is an assertion that there is no tuple matching
114		* a particular key. This is just as useful as a normal entry so far as
115		* avoiding catalog searches is concerned. Management of positive and
116		* negative entries is identical.
117		*/
118		int refcount; /* number of active references */
119		bool dead; /* dead but not yet removed? */
120		bool negative; /* negative cache entry? */
121		HeapTupleData tuple; /* tuple management header */
122
123		/*
124		* The tuple may also be a member of at most one CatCList. (If a single
125		* catcache is list-searched with varying numbers of keys, we may have to
126		* make multiple entries for the same tuple because of this restriction.
127		* Currently, that's not expected to be common, so we accept the potential
128		* inefficiency.)
129		*/
130		struct catclist c_list; / containing CatCList, or NULL if none */
131
132		CatCache my_cache; / link to owning catcache */
133		/* properly aligned tuple data follows, unless a negative entry */
134		} CatCTup;
135
136
137		/*
138		* A CatCList describes the result of a partial search, ie, a search using
139		* only the first K key columns of an N-key cache. We store the keys used
140		* into the keys attribute to represent the stored key set. The CatCList
141		* object contains links to cache entries for all the table rows satisfying
142		* the partial key. (Note: none of these will be negative cache entries.)
143		*
144		* A CatCList is only a member of a per-cache list; we do not currently
145		* divide them into hash buckets.
146		*
147		* A list marked "dead" must not be returned by subsequent searches.
148		* However, it won't be physically deleted from the cache until its
149		* refcount goes to zero. (A list should be marked dead if any of its
150		* member entries are dead.)
151		*
152		* If "ordered" is true then the member tuples appear in the order of the
153		* cache's underlying index. This will be true in normal operation, but
154		* might not be true during bootstrap or recovery operations. (namespace.c
155		* is able to save some cycles when it is true.)
156		*/
157		typedef struct catclist
158		{
159		int cl_magic; /* for identifying CatCList entries */
160	714k	#define CL_MAGIC 0x52765103
161
162		uint32 hash_value; /* hash value for lookup keys */
163
164		dlist_node cache_elem; /* list member of per-catcache list */
165
166		/*
167		* Lookup keys for the entry, with the first nkeys elements being valid.
168		* All by-reference are separately allocated.
169		*/
170		Datum keys[CATCACHE_MAXKEYS];
171
172		int refcount; /* number of active references */
173		bool dead; /* dead but not yet removed? */
174		bool ordered; /* members listed in index order? */
175		short nkeys; /* number of lookup keys specified */
176		int n_members; /* number of member tuples */
177		CatCache my_cache; / link to owning catcache */
178		CatCTup members[FLEXIBLE_ARRAY_MEMBER]; / members */
179		} CatCList;
180
181
182		typedef struct catcacheheader
183		{
184		slist_head ch_caches; /* head of list of CatCache structs */
185		int ch_ntup; /* # of tuples in all caches */
186		} CatCacheHeader;
187
188
189		/* this extern duplicates utils/memutils.h... */
190		extern PGDLLIMPORT MemoryContext CacheMemoryContext;
191
192		extern void CreateCacheMemoryContext(void);
193
194		extern CatCache *InitCatCache(int id, Oid reloid, Oid indexoid,
195		int nkeys, const int *key,
196		int nbuckets);
197
198		extern void InitCatCachePhase2(CatCache *cache, bool touch_index);
199
200		extern HeapTuple SearchCatCache(CatCache *cache,
201		Datum v1, Datum v2, Datum v3, Datum v4);
202		extern HeapTuple SearchCatCache1(CatCache *cache,
203		Datum v1);
204		extern HeapTuple SearchCatCache2(CatCache *cache,
205		Datum v1, Datum v2);
206		extern HeapTuple SearchCatCache3(CatCache *cache,
207		Datum v1, Datum v2, Datum v3);
208		extern HeapTuple SearchCatCache4(CatCache *cache,
209		Datum v1, Datum v2, Datum v3, Datum v4);
210		extern void ReleaseCatCache(HeapTuple tuple);
211
212		extern uint32 GetCatCacheHashValue(CatCache *cache,
213		Datum v1, Datum v2,
214		Datum v3, Datum v4);
215
216		/* Used in IsYugaByteEnabled() mode only */
217		extern void SetCatCacheTuple(CatCache *cache, HeapTuple tup, TupleDesc tupdesc);
218		extern void SetCatCacheList(CatCache cache, int nkeys, List fnlist);
219
220		extern CatCList SearchCatCacheList(CatCache cache, int nkeys,
221		Datum v1, Datum v2,
222		Datum v3);
223		extern void ReleaseCatCacheList(CatCList *list);
224
225		extern void ResetCatalogCaches(void);
226		extern void CatalogCacheFlushCatalog(Oid catId);
227		extern void CatCacheInvalidate(CatCache *cache, uint32 hashValue);
228		extern void PrepareToInvalidateCacheTuple(Relation relation,
229		HeapTuple tuple,
230		HeapTuple newtuple,
231		void (*function) (int, uint32, Oid));
232		extern bool RelationHasCachedLists(Relation relation);
233
234		extern void PrintCatCacheLeakWarning(HeapTuple tuple);
235		extern void PrintCatCacheListLeakWarning(CatCList *list);
236
237		extern long GetCatCacheMisses();
238
239		#endif /* CATCACHE_H */