On Mon, Sep 9, 2013 at 07:39:00PM -0400, Bruce Momjian wrote:
> > In the case of tablespaces, I should have thought you could keep a
> > hash table of the names and just store an entry id in the table
> > structure. But that's just my speculation without actually looking
> > at the code, so don't take my word for it :-)
>
> Yes, please feel free to improve the code. I improved pg_upgrade CPU
> usage for a lerge number of objects, but never thought to look at memory
> usage. It would be a big win to just palloc/pfree the memory, rather
> than allocate tones of memory. If you don't get to it, I will in a few
> weeks.
Advertising
Thanks you for pointing out this problem. I have researched the cause
and the major problem was that I was allocating the maximum path length
in a struct rather than allocating just the length I needed, and was not
reusing string pointers that I knew were not going to change.
The updated attached patch significantly decreases memory consumption:
tables orig patch % decrease
----
1 27,168 kB 27,168 kB 0
1k 46,136 kB 27,920 kB 39
2k 65,224 kB 28,796 kB 56
4k 103,276 kB 30,472 kB 70
8k 179,512 kB 33,900 kB 81
16k 331,860 kB 40,788 kB 88
32k 636,544 kB 54,572 kB 91
64k 1,245,920 kB 81,876 kB 93
As you can see, a database with 64k tables shows a 93% decrease in
memory use. I plan to apply this for PG 9.4.
--
Bruce Momjian <br...@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ Everyone has their own god. +
diff --git a/contrib/pg_upgrade/check.c b/contrib/pg_upgrade/check.c
new file mode 100644
index f04707f..acf8660
*** a/contrib/pg_upgrade/check.c
--- b/contrib/pg_upgrade/check.c
*************** create_script_for_old_cluster_deletion(c
*** 707,726 ****
fprintf(script, "\n");
/* remove PG_VERSION? */
if (GET_MAJOR_VERSION(old_cluster.major_version) <= 804)
! fprintf(script, RM_CMD " %s%s%cPG_VERSION\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
- fix_path_separator(old_cluster.tablespace_suffix),
PATH_SEPARATOR);
for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
! {
! fprintf(script, RMDIR_CMD " %s%s%c%d\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
- fix_path_separator(old_cluster.tablespace_suffix),
PATH_SEPARATOR, old_cluster.dbarr.dbs[dbnum].db_oid);
- }
}
else
/*
* Simply delete the tablespace directory, which might be ".old"
--- 707,724 ----
fprintf(script, "\n");
/* remove PG_VERSION? */
if (GET_MAJOR_VERSION(old_cluster.major_version) <= 804)
! fprintf(script, RM_CMD " %s%cPG_VERSION\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
PATH_SEPARATOR);
for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
! fprintf(script, RMDIR_CMD " %s%c%d\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
PATH_SEPARATOR, old_cluster.dbarr.dbs[dbnum].db_oid);
}
else
+ {
+ char *suffix_path = pg_strdup(old_cluster.tablespace_suffix);
/*
* Simply delete the tablespace directory, which might be ".old"
*************** create_script_for_old_cluster_deletion(c
*** 728,734 ****
*/
fprintf(script, RMDIR_CMD " %s%s\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
! fix_path_separator(old_cluster.tablespace_suffix));
}
fclose(script);
--- 726,734 ----
*/
fprintf(script, RMDIR_CMD " %s%s\n",
fix_path_separator(os_info.old_tablespaces[tblnum]),
! fix_path_separator(suffix_path));
! pfree(suffix_path);
! }
}
fclose(script);
diff --git a/contrib/pg_upgrade/info.c b/contrib/pg_upgrade/info.c
new file mode 100644
index 3d0dd1a..fd083de
*** a/contrib/pg_upgrade/info.c
--- b/contrib/pg_upgrade/info.c
*************** create_rel_filename_map(const char *old_
*** 108,127 ****
* relation belongs to the default tablespace, hence relfiles should
* exist in the data directories.
*/
! strlcpy(map->old_tablespace, old_data, sizeof(map->old_tablespace));
! strlcpy(map->new_tablespace, new_data, sizeof(map->new_tablespace));
! strlcpy(map->old_tablespace_suffix, "/base", sizeof(map->old_tablespace_suffix));
! strlcpy(map->new_tablespace_suffix, "/base", sizeof(map->new_tablespace_suffix));
}
else
{
/* relation belongs to a tablespace, so use the tablespace location */
! strlcpy(map->old_tablespace, old_rel->tablespace, sizeof(map->old_tablespace));
! strlcpy(map->new_tablespace, new_rel->tablespace, sizeof(map->new_tablespace));
! strlcpy(map->old_tablespace_suffix, old_cluster.tablespace_suffix,
! sizeof(map->old_tablespace_suffix));
! strlcpy(map->new_tablespace_suffix, new_cluster.tablespace_suffix,
! sizeof(map->new_tablespace_suffix));
}
map->old_db_oid = old_db->db_oid;
--- 108,125 ----
* relation belongs to the default tablespace, hence relfiles should
* exist in the data directories.
*/
! map->old_tablespace = old_data;
! map->new_tablespace = new_data;
! map->old_tablespace_suffix = "/base";
! map->new_tablespace_suffix = "/base";
}
else
{
/* relation belongs to a tablespace, so use the tablespace location */
! map->old_tablespace = old_rel->tablespace;
! map->new_tablespace = new_rel->tablespace;
! map->old_tablespace_suffix = old_cluster.tablespace_suffix;
! map->new_tablespace_suffix = new_cluster.tablespace_suffix;
}
map->old_db_oid = old_db->db_oid;
*************** get_db_infos(ClusterInfo *cluster)
*** 231,237 ****
{
dbinfos[tupnum].db_oid = atooid(PQgetvalue(res, tupnum, i_oid));
dbinfos[tupnum].db_name = pg_strdup(PQgetvalue(res, tupnum, i_datname));
! snprintf(dbinfos[tupnum].db_tblspace, sizeof(dbinfos[tupnum].db_tblspace), "%s",
PQgetvalue(res, tupnum, i_spclocation));
}
PQclear(res);
--- 229,235 ----
{
dbinfos[tupnum].db_oid = atooid(PQgetvalue(res, tupnum, i_oid));
dbinfos[tupnum].db_name = pg_strdup(PQgetvalue(res, tupnum, i_datname));
! snprintf(dbinfos[tupnum].db_tablespace, sizeof(dbinfos[tupnum].db_tablespace), "%s",
PQgetvalue(res, tupnum, i_spclocation));
}
PQclear(res);
*************** get_rel_infos(ClusterInfo *cluster, DbIn
*** 264,269 ****
--- 262,268 ----
int num_rels = 0;
char *nspname = NULL;
char *relname = NULL;
+ char *tablespace = NULL;
int i_spclocation,
i_nspname,
i_relname,
*************** get_rel_infos(ClusterInfo *cluster, DbIn
*** 271,276 ****
--- 270,276 ----
i_relfilenode,
i_reltablespace;
char query[QUERY_ALLOC];
+ char *last_namespace = NULL, *last_tablespace = NULL;
/*
* pg_largeobject contains user data that does not appear in pg_dumpall
*************** get_rel_infos(ClusterInfo *cluster, DbIn
*** 366,391 ****
for (relnum = 0; relnum < ntups; relnum++)
{
RelInfo *curr = &relinfos[num_rels++];
- const char *tblspace;
curr->reloid = atooid(PQgetvalue(res, relnum, i_oid));
nspname = PQgetvalue(res, relnum, i_nspname);
! curr->nspname = pg_strdup(nspname);
relname = PQgetvalue(res, relnum, i_relname);
curr->relname = pg_strdup(relname);
curr->relfilenode = atooid(PQgetvalue(res, relnum, i_relfilenode));
if (atooid(PQgetvalue(res, relnum, i_reltablespace)) != 0)
! /* Might be "", meaning the cluster default location. */
! tblspace = PQgetvalue(res, relnum, i_spclocation);
! else
! /* A zero reltablespace indicates the database tablespace. */
! tblspace = dbinfo->db_tblspace;
! strlcpy(curr->tablespace, tblspace, sizeof(curr->tablespace));
}
PQclear(res);
--- 366,418 ----
for (relnum = 0; relnum < ntups; relnum++)
{
RelInfo *curr = &relinfos[num_rels++];
curr->reloid = atooid(PQgetvalue(res, relnum, i_oid));
nspname = PQgetvalue(res, relnum, i_nspname);
! curr->nsp_alloc = false;
!
! /*
! * Many of the namespace and tablespace strings are identical,
! * so we try to reuse the allocated string pointers where possible
! * to reduce memory consumption.
! */
! /* Can we reuse the previous string allocation? */
! if (last_namespace && strcmp(nspname, last_namespace) == 0)
! curr->nspname = last_namespace;
! else
! {
! last_namespace = curr->nspname = pg_strdup(nspname);
! curr->nsp_alloc = true;
! }
relname = PQgetvalue(res, relnum, i_relname);
curr->relname = pg_strdup(relname);
curr->relfilenode = atooid(PQgetvalue(res, relnum, i_relfilenode));
+ curr->tblsp_alloc = false;
+ /* Is the tablespace oid non-zero? */
if (atooid(PQgetvalue(res, relnum, i_reltablespace)) != 0)
! {
! /*
! * The tablespace location might be "", meaning the cluster
! * default location, i.e. pg_default or pg_global.
! */
! tablespace = PQgetvalue(res, relnum, i_spclocation);
! /* Can we reuse the previous string allocation? */
! if (last_tablespace && strcmp(tablespace, last_tablespace) == 0)
! curr->tablespace = last_tablespace;
! else
! {
! last_tablespace = curr->tablespace = pg_strdup(tablespace);
! curr->tblsp_alloc = true;
! }
! }
! else
! /* A zero reltablespace oid indicates the database tablespace. */
! curr->tablespace = dbinfo->db_tablespace;
}
PQclear(res);
*************** free_rel_infos(RelInfoArr *rel_arr)
*** 419,426 ****
for (relnum = 0; relnum < rel_arr->nrels; relnum++)
{
! pg_free(rel_arr->rels[relnum].nspname);
pg_free(rel_arr->rels[relnum].relname);
}
pg_free(rel_arr->rels);
rel_arr->nrels = 0;
--- 446,456 ----
for (relnum = 0; relnum < rel_arr->nrels; relnum++)
{
! if (rel_arr->rels[relnum].nsp_alloc)
! pg_free(rel_arr->rels[relnum].nspname);
pg_free(rel_arr->rels[relnum].relname);
+ if (rel_arr->rels[relnum].tblsp_alloc)
+ pg_free(rel_arr->rels[relnum].tablespace);
}
pg_free(rel_arr->rels);
rel_arr->nrels = 0;
diff --git a/contrib/pg_upgrade/pg_upgrade.h b/contrib/pg_upgrade/pg_upgrade.h
new file mode 100644
index de487bc..389ec93
*** a/contrib/pg_upgrade/pg_upgrade.h
--- b/contrib/pg_upgrade/pg_upgrade.h
*************** typedef struct
*** 127,133 ****
Oid reloid; /* relation oid */
Oid relfilenode; /* relation relfile node */
/* relation tablespace path, or "" for the cluster default */
! char tablespace[MAXPGPATH];
} RelInfo;
typedef struct
--- 127,135 ----
Oid reloid; /* relation oid */
Oid relfilenode; /* relation relfile node */
/* relation tablespace path, or "" for the cluster default */
! char *tablespace;
! bool nsp_alloc;
! bool tblsp_alloc;
} RelInfo;
typedef struct
*************** typedef struct
*** 141,150 ****
*/
typedef struct
{
! char old_tablespace[MAXPGPATH];
! char new_tablespace[MAXPGPATH];
! char old_tablespace_suffix[MAXPGPATH];
! char new_tablespace_suffix[MAXPGPATH];
Oid old_db_oid;
Oid new_db_oid;
--- 143,152 ----
*/
typedef struct
{
! const char *old_tablespace;
! const char *new_tablespace;
! const char *old_tablespace_suffix;
! const char *new_tablespace_suffix;
Oid old_db_oid;
Oid new_db_oid;
*************** typedef struct
*** 166,172 ****
{
Oid db_oid; /* oid of the database */
char *db_name; /* database name */
! char db_tblspace[MAXPGPATH]; /* database default tablespace path */
RelInfoArr rel_arr; /* array of all user relinfos */
} DbInfo;
--- 168,174 ----
{
Oid db_oid; /* oid of the database */
char *db_name; /* database name */
! char db_tablespace[MAXPGPATH]; /* database default tablespace path */
RelInfoArr rel_arr; /* array of all user relinfos */
} DbInfo;
*************** typedef struct
*** 256,262 ****
Oid pg_database_oid; /* OID of pg_database relation */
Oid install_role_oid; /* OID of connected role */
Oid role_count; /* number of roles defined in the cluster */
! char *tablespace_suffix; /* directory specification */
} ClusterInfo;
--- 258,264 ----
Oid pg_database_oid; /* OID of pg_database relation */
Oid install_role_oid; /* OID of connected role */
Oid role_count; /* number of roles defined in the cluster */
! const char *tablespace_suffix; /* directory specification */
} ClusterInfo;
--
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