diff -Nacr pgsql.orig/doc/src/sgml/catalogs.sgml pgsql/doc/src/sgml/catalogs.sgml *** pgsql.orig/doc/src/sgml/catalogs.sgml Mon Mar 7 12:20:17 2005 --- pgsql/doc/src/sgml/catalogs.sgml Tue Mar 8 12:03:50 2005 *************** *** 3875,3880 **** --- 3875,3885 ---- + pg_buffercache + shared buffer cache + + + pg_indexes indexes *************** *** 3917,3922 **** --- 3922,4021 ---- + + + + <structname>pg_buffercache</structname> + + + pg_buffercache + + + The view pg_buffercache provides access to + some information from the shared buffer cache. + + + + There is one row for each buffer in the shared cache. Unused buffers are + shown with all fields null except bufferid. + Because the cache is shared by all the databases, there are pages from + relations not belonging to the current database. + + + + + <structname>pg_buffercache</structname> Columns + + + + + Name + Type + References + Description + + + + + bufferid + integer + + + The buffer number. This is numbered 1 to shared_buffers. + + + + relfilenode + oid + pg_class.relfilenode + + The on-disk file for the relation that this page came from. + + + + reltablespace + oid + + pg_tablespace.oid + + Tablespace the corresponding relation is in. + + + reldatabase + oid + pg_database.oid + + Database the corresponding relation belongs to, or zero if the + relation is a globally-shared table + + + relblocknumber + numeric + + + The page offset within the relation that this buffer page is for. + + + + isdirty + bool + + True if the buffer is dirty. + + + + +
+ + + When the pg_buffercache view is accessed, + internal buffer manager locks are taken, and a copy of the buffer cache data + is made for the view to display. This ensures that the view produces a + consistent set of results, while not blocking normal buffer activity longer + than necessary. Nonetheless there could be some impact on database + performance if this view is read often. + + diff -Nacr pgsql.orig/src/backend/catalog/system_views.sql pgsql/src/backend/catalog/system_views.sql *** pgsql.orig/src/backend/catalog/system_views.sql Fri Mar 4 14:23:09 2005 --- pgsql/src/backend/catalog/system_views.sql Tue Mar 8 11:45:39 2005 *************** *** 277,279 **** --- 277,285 ---- DO INSTEAD NOTHING; GRANT SELECT, UPDATE ON pg_settings TO PUBLIC; + + CREATE VIEW pg_buffercache AS + SELECT P.* FROM pg_buffercache_pages() AS P + (bufferid integer, relfilenode oid, reltablespace oid, reldatabase oid, + relblocknumber numeric(10), isdirty bool); + diff -Nacr pgsql.orig/src/backend/utils/adt/Makefile pgsql/src/backend/utils/adt/Makefile *** pgsql.orig/src/backend/utils/adt/Makefile Mon Mar 7 10:16:24 2005 --- pgsql/src/backend/utils/adt/Makefile Tue Mar 8 11:44:10 2005 *************** *** 24,30 **** tid.o timestamp.o varbit.o varchar.o varlena.o version.o xid.o \ network.o mac.o inet_net_ntop.o inet_net_pton.o \ ri_triggers.o pg_lzcompress.o pg_locale.o formatting.o \ ! ascii.o quote.o pgstatfuncs.o encode.o like.o: like.c like_match.c --- 24,30 ---- tid.o timestamp.o varbit.o varchar.o varlena.o version.o xid.o \ network.o mac.o inet_net_ntop.o inet_net_pton.o \ ri_triggers.o pg_lzcompress.o pg_locale.o formatting.o \ ! ascii.o quote.o pgstatfuncs.o encode.o buffercache.o like.o: like.c like_match.c diff -Nacr pgsql.orig/src/backend/utils/adt/buffercache.c pgsql/src/backend/utils/adt/buffercache.c *** pgsql.orig/src/backend/utils/adt/buffercache.c Thu Jan 1 12:00:00 1970 --- pgsql/src/backend/utils/adt/buffercache.c Tue Mar 8 11:48:56 2005 *************** *** 0 **** --- 1,237 ---- + /*------------------------------------------------------------------------- + * + * buffercache.c + * display some contents of the buffer cache + * + * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * $PostgreSQL$ + *------------------------------------------------------------------------- + */ + #include "postgres.h" + #include "funcapi.h" + #include "catalog/pg_type.h" + #include "storage/buf_internals.h" + #include "storage/bufmgr.h" + #include "utils/relcache.h" + #include "utils/builtins.h" + + + #define NUM_BUFFERCACHE_PAGES_ELEM 6 + + + /* + * Record structure holding the to be exposed cache data. + */ + typedef struct + { + uint32 bufferid; + Oid relfilenode; + Oid reltablespace; + Oid reldatabase; + BlockNumber blocknum; + bool isvalid; + bool isdirty; + + } BufferCachePagesRec; + + + /* + * Function context for data persisting over repeated calls. + */ + typedef struct + { + AttInMetadata *attinmeta; + BufferCachePagesRec *record; + char *values[NUM_BUFFERCACHE_PAGES_ELEM]; + } BufferCachePagesContext; + + + /* + * Function returning data from the shared buffer cache - buffer number, + * relation node/tablespace/database/blocknum and dirty indicator. + */ + Datum + pg_buffercache_pages(PG_FUNCTION_ARGS) + { + FuncCallContext *funcctx; + Datum result; + MemoryContext oldcontext; + BufferCachePagesContext *fctx; /* User function context. */ + TupleDesc tupledesc; + HeapTuple tuple; + + if (SRF_IS_FIRSTCALL()) + { + RelFileNode rnode; + uint32 i; + BufferDesc *bufHdr; + + + funcctx = SRF_FIRSTCALL_INIT(); + + /* Switch context when allocating stuff to be used in later calls */ + oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx); + + /* construct a tuple to return */ + tupledesc = CreateTemplateTupleDesc(NUM_BUFFERCACHE_PAGES_ELEM, false); + TupleDescInitEntry(tupledesc, (AttrNumber) 1, "bufferid", + INT4OID, -1, 0); + TupleDescInitEntry(tupledesc, (AttrNumber) 2, "relfilenode", + OIDOID, -1, 0); + TupleDescInitEntry(tupledesc, (AttrNumber) 3, "reltablespace", + OIDOID, -1, 0); + TupleDescInitEntry(tupledesc, (AttrNumber) 4, "reldatabase", + OIDOID, -1, 0); + TupleDescInitEntry(tupledesc, (AttrNumber) 5, "relblockbumber", + NUMERICOID, -1, 0); + TupleDescInitEntry(tupledesc, (AttrNumber) 6, "isdirty", + BOOLOID, -1, 0); + + /* Generate attribute metadata needed later to produce tuples */ + funcctx->attinmeta = TupleDescGetAttInMetadata(tupledesc); + + /* + * Create a function context for cross-call persistence + * and initialize the buffer counters. + */ + fctx = (BufferCachePagesContext *) palloc(sizeof(BufferCachePagesContext)); + funcctx->max_calls = NBuffers; + funcctx->user_fctx = fctx; + + + /* Allocate NBuffers worth of BufferCachePagesRec records. */ + fctx->record = (BufferCachePagesRec *) palloc(sizeof(BufferCachePagesRec) * NBuffers); + + /* allocate the strings for tuple formation */ + fctx->values[0] = (char *) palloc(3 * sizeof(uint32) + 1); + fctx->values[1] = (char *) palloc(3 * sizeof(uint32) + 1); + fctx->values[2] = (char *) palloc(3 * sizeof(uint32) + 1); + fctx->values[3] = (char *) palloc(3 * sizeof(uint32) + 1); + fctx->values[4] = (char *) palloc(3 * sizeof(uint32) + 1); + fctx->values[5] = (char *) palloc(10); + + + /* Return to original context when allocating transient memory */ + MemoryContextSwitchTo(oldcontext); + + + /* + * Lock Buffer map and scan though all the buffers, saving the + * relevant fields in the fctx->record structure. + */ + LWLockAcquire(BufMappingLock, LW_SHARED); + + for (i = 0, bufHdr = BufferDescriptors; i < NBuffers; i++, bufHdr++) + { + /* Lock each buffer header before inspecting. */ + LockBufHdr(bufHdr); + + rnode = bufHdr->tag.rnode; + + fctx->record[i].bufferid = BufferDescriptorGetBuffer(bufHdr); + fctx->record[i].relfilenode = rnode.relNode; + fctx->record[i].reltablespace = rnode.spcNode; + fctx->record[i].reldatabase = rnode.dbNode; + fctx->record[i].blocknum = bufHdr->tag.blockNum; + + if ( bufHdr->flags & BM_DIRTY) + { + fctx->record[i].isdirty = true; + } + else + { + fctx->record[i].isdirty = false; + } + + /* Note if the buffer is valid, and has storage created */ + if ( (bufHdr->flags & BM_VALID) && (bufHdr->flags & BM_TAG_VALID)) + { + fctx->record[i].isvalid = true; + } + else + { + fctx->record[i].isvalid = false; + } + + UnlockBufHdr(bufHdr); + + } + + /* Release Buffer map. */ + LWLockRelease(BufMappingLock); + } + + funcctx = SRF_PERCALL_SETUP(); + + /* Get the saved state */ + fctx = funcctx->user_fctx; + + + if (funcctx->call_cntr < funcctx->max_calls) + { + uint32 i = funcctx->call_cntr; + char *values[NUM_BUFFERCACHE_PAGES_ELEM]; + int j; + + /* + * Use a temporary values array, initially pointing to + * fctx->values, so it can be reassigned w/o losing the storage + * for subsequent calls. + */ + for (j = 0; j < NUM_BUFFERCACHE_PAGES_ELEM; j++) + { + values[j] = fctx->values[j]; + } + + + /* + * Set all fields except the bufferid to null if the buffer is + * unused or not valid. + */ + if (fctx->record[i].blocknum == InvalidBlockNumber || + fctx->record[i].isvalid == false ) + { + + sprintf(values[0], "%u", fctx->record[i].bufferid); + values[1] = NULL; + values[2] = NULL; + values[3] = NULL; + values[4] = NULL; + values[5] = NULL; + + } + else + { + + sprintf(values[0], "%u", fctx->record[i].bufferid); + sprintf(values[1], "%u", fctx->record[i].relfilenode); + sprintf(values[2], "%u", fctx->record[i].reltablespace); + sprintf(values[3], "%u", fctx->record[i].reldatabase); + sprintf(values[4], "%u", fctx->record[i].blocknum); + if (fctx->record[i].isdirty) + { + strcpy(values[5], "true"); + } + else + { + strcpy(values[5], "false"); + } + + } + + + /* Build and return the tuple. */ + tuple = BuildTupleFromCStrings(funcctx->attinmeta, values); + result = HeapTupleGetDatum(tuple); + + + SRF_RETURN_NEXT(funcctx, result); + } + else + SRF_RETURN_DONE(funcctx); + } + diff -Nacr pgsql.orig/src/include/catalog/pg_proc.h pgsql/src/include/catalog/pg_proc.h *** pgsql.orig/src/include/catalog/pg_proc.h Fri Mar 4 14:24:20 2005 --- pgsql/src/include/catalog/pg_proc.h Tue Mar 8 11:46:06 2005 *************** *** 3615,3620 **** --- 3615,3622 ---- DATA(insert OID = 2558 ( int4 PGNSP PGUID 12 f f t f i 1 23 "16" _null_ bool_int4 - _null_ )); DESCR("convert boolean to int4"); + /* builtin for cache internals view */ + DATA(insert OID = 2510 ( pg_buffercache_pages PGNSP PGUID 12 f f t t v 0 2249 "" _null_ pg_buffercache_pages - _null_ )); /* * Symbolic values for provolatile column: these indicate whether the result diff -Nacr pgsql.orig/src/include/utils/builtins.h pgsql/src/include/utils/builtins.h *** pgsql.orig/src/include/utils/builtins.h Fri Mar 4 14:24:31 2005 --- pgsql/src/include/utils/builtins.h Tue Mar 8 11:46:26 2005 *************** *** 823,826 **** --- 823,829 ---- /* catalog/pg_conversion.c */ extern Datum pg_convert_using(PG_FUNCTION_ARGS); + /* cache dump */ + extern Datum pg_buffercache_pages(PG_FUNCTION_ARGS); + #endif /* BUILTINS_H */ diff -Nacr pgsql.orig/src/test/regress/expected/rules.out pgsql/src/test/regress/expected/rules.out *** pgsql.orig/src/test/regress/expected/rules.out Tue Mar 8 13:00:00 2005 --- pgsql/src/test/regress/expected/rules.out Tue Mar 8 12:59:24 2005 *************** *** 1275,1280 **** --- 1275,1281 ---- viewname | definition --------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- iexit | SELECT ih.name, ih.thepath, interpt_pp(ih.thepath, r.thepath) AS exit FROM ihighway ih, ramp r WHERE (ih.thepath ## r.thepath); + pg_buffercache | SELECT p.bufferid, p.relfilenode, p.reltablespace, p.reldatabase, p.relblocknumber, p.isdirty FROM pg_buffercache_pages() p(bufferid integer, relfilenode oid, reltablespace oid, reldatabase oid, relblocknumbernumeric(10,0), isdirty boolean); pg_indexes | SELECT n.nspname AS schemaname, c.relname AS tablename, i.relname AS indexname, t.spcname AS "tablespace", pg_get_indexdef(i.oid) AS indexdef FROM ((((pg_index x JOIN pg_class c ON ((c.oid = x.indrelid))) JOIN pg_class i ON ((i.oid = x.indexrelid))) LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace))) LEFT JOIN pg_tablespace t ON ((t.oid = i.reltablespace))) WHERE ((c.relkind = 'r'::"char") AND (i.relkind = 'i'::"char")); pg_locks | SELECT l.relation, l."database", l."transaction", l.pid, l."mode", l.granted FROM pg_lock_status() l(relation oid, "database" oid, "transaction" xid, pid integer, "mode" text, granted boolean); pg_rules | SELECT n.nspname AS schemaname, c.relname AS tablename, r.rulename, pg_get_ruledef(r.oid) AS definition FROM ((pg_rewrite r JOIN pg_class c ON ((c.oid = r.ev_class))) LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace))) WHERE (r.rulename <> '_RETURN'::name); *************** *** 1314,1320 **** shoelace_obsolete | SELECT shoelace.sl_name, shoelace.sl_avail, shoelace.sl_color, shoelace.sl_len, shoelace.sl_unit, shoelace.sl_len_cm FROM shoelace WHERE (NOT (EXISTS (SELECT shoe.shoename FROM shoe WHERE (shoe.slcolor = shoelace.sl_color)))); street | SELECT r.name, r.thepath, c.cname FROM ONLY road r, real_city c WHERE (c.outline ## r.thepath); toyemp | SELECT emp.name, emp.age, emp."location", (12 * emp.salary) AS annualsal FROM emp; ! (40 rows) SELECT tablename, rulename, definition FROM pg_rules ORDER BY tablename, rulename; --- 1315,1321 ---- shoelace_obsolete | SELECT shoelace.sl_name, shoelace.sl_avail, shoelace.sl_color, shoelace.sl_len, shoelace.sl_unit, shoelace.sl_len_cm FROM shoelace WHERE (NOT (EXISTS (SELECT shoe.shoename FROM shoe WHERE (shoe.slcolor = shoelace.sl_color)))); street | SELECT r.name, r.thepath, c.cname FROM ONLY road r, real_city c WHERE (c.outline ## r.thepath); toyemp | SELECT emp.name, emp.age, emp."location", (12 * emp.salary) AS annualsal FROM emp; ! (41 rows) SELECT tablename, rulename, definition FROM pg_rules ORDER BY tablename, rulename;