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Buffer manager modifications to keep a local buffer-dirtied bit as well

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as a shared dirtybit for each shared buffer.  The shared dirtybit still
controls writing the buffer, but the local bit controls whether we need
to fsync the buffer's file.  This arrangement fixes a bug that allowed
some required fsyncs to be missed, and should improve performance as well.
For more info see my post of same date on pghackers.
This commit is contained in:
Tom Lane
2000-04-09 04:43:20 +00:00
parent 9c38a8d296
commit 1f6d8b90b8
13 changed files with 955 additions and 435 deletions
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74
src/backend/catalog/catalog.c
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@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/catalog/catalog.c,v 1.30 2000/01/26 05:56:10 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/catalog/catalog.c,v 1.31 2000/04/09 04:43:15 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -23,25 +23,87 @@
#include "utils/syscache.h"
/*
* relpath - path to the relation
* Perhaps this should be in-line code in relopen().
* relpath - construct path to a relation's file
*
* Note that this only works with relations that are visible to the current
* backend, ie, either in the current database or shared system relations.
*
* Result is a palloc'd string.
*/
char *
relpath(const char *relname)
{
char *path;
size_t bufsize = 0;
if (IsSharedSystemRelationName(relname))
{
bufsize = strlen(DataDir) + sizeof(NameData) + 2;
/* Shared system relations live in DataDir */
size_t bufsize = strlen(DataDir) + sizeof(NameData) + 2;
path = (char *) palloc(bufsize);
snprintf(path, bufsize, "%s/%s", DataDir, relname);
snprintf(path, bufsize, "%s%c%s", DataDir, SEP_CHAR, relname);
return path;
}
/*
* If it is in the current database, assume it is in current working
* directory. NB: this does not work during bootstrap!
*/
return pstrdup(relname);
}
/*
* relpath_blind - construct path to a relation's file
*
* Construct the path using only the info available to smgrblindwrt,
* namely the names and OIDs of the database and relation. (Shared system
* relations are identified with dbid = 0.) Note that we may have to
* access a relation belonging to a different database!
*
* Result is a palloc'd string.
*/
char *
relpath_blind(const char *dbname, const char *relname,
Oid dbid, Oid relid)
{
char *path;
if (dbid == (Oid) 0)
{
/* Shared system relations live in DataDir */
path = (char *) palloc(strlen(DataDir) + sizeof(NameData) + 2);
sprintf(path, "%s%c%s", DataDir, SEP_CHAR, relname);
}
else if (dbid == MyDatabaseId)
{
/* XXX why is this inconsistent with relpath() ? */
path = (char *) palloc(strlen(DatabasePath) + sizeof(NameData) + 2);
sprintf(path, "%s%c%s", DatabasePath, SEP_CHAR, relname);
}
else
{
/* this is work around only !!! */
char dbpathtmp[MAXPGPATH];
Oid id;
char *dbpath;
GetRawDatabaseInfo(dbname, &id, dbpathtmp);
if (id != dbid)
elog(FATAL, "relpath_blind: oid of db %s is not %u",
dbname, dbid);
dbpath = ExpandDatabasePath(dbpathtmp);
if (dbpath == NULL)
elog(FATAL, "relpath_blind: can't expand path for db %s",
dbname);
path = (char *) palloc(strlen(dbpath) + sizeof(NameData) + 2);
sprintf(path, "%s%c%s", dbpath, SEP_CHAR, relname);
pfree(dbpath);
}
return path;
}
/*
* IsSystemRelationName
* True iff name is the name of a system catalog relation.