Remove geqo_random_seed parameter. Having geqo reset the global random()

sequence every time it's called is bogus --- it interferes with user
control over the seed, and actually decreases randomness overall
(because a seed based on time(NULL) is pretty predictable).  If you really
want a reproducible result from geqo, do 'set seed = 0' before planning
a query.

diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 9bbecfa76bbe063b6d6d5e8756f0540de743bf73..425036d81d350587f6adc4193858fd9546e2e2e6 100644 (file)
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.203 2003/09/05 16:13:38 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.204 2003/09/07 15:26:45 tgl Exp $
 -->
 
 <Chapter Id="runtime">
@@ -1438,7 +1438,6 @@ SET ENABLE_SEQSCAN TO OFF;
       <term><varname>GEQO_EFFORT</varname> (<type>integer</type>)</term>
       <term><varname>GEQO_GENERATIONS</varname> (<type>integer</type>)</term>
       <term><varname>GEQO_POOL_SIZE</varname> (<type>integer</type>)</term>
-      <term><varname>GEQO_RANDOM_SEED</varname> (<type>integer</type>)</term>
       <term><varname>GEQO_SELECTION_BIAS</varname> (<type>floating point</type>)</term>
       <listitem>
        <para>
@@ -1455,9 +1454,7 @@ SET ENABLE_SEQSCAN TO OFF;
         is roughly proportional to the sum of pool size and generations.
         The selection bias is the selective pressure within the
         population. Values can be from 1.50 to 2.00; the latter is the
-        default. The random seed can be set to get reproducible results
-        from the algorithm. If it is set to -1 then the algorithm
-        behaves non-deterministically.
+        default.
        </para>
       </listitem>
      </varlistentry>

diff --git a/src/backend/optimizer/geqo/geqo_main.c b/src/backend/optimizer/geqo/geqo_main.c
index d657fdf8db64f22ab1197642a10c8eb7d746e85c..031cd665d4f16d732a99fb4ca8e5981a14f66660 100644 (file)
--- a/src/backend/optimizer/geqo/geqo_main.c
+++ b/src/backend/optimizer/geqo/geqo_main.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Header: /cvsroot/pgsql/src/backend/optimizer/geqo/geqo_main.c,v 1.39 2003/08/12 18:23:20 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/geqo/geqo_main.c,v 1.40 2003/09/07 15:26:52 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -41,7 +41,6 @@ int                   Geqo_pool_size;
 int                    Geqo_effort;
 int                    Geqo_generations;
 double         Geqo_selection_bias;
-int                    Geqo_random_seed;
 
 
 static int     gimme_pool_size(int nr_rel);
@@ -96,13 +95,6 @@ geqo(Query *root, int number_of_rels, List *initial_rels)
        number_generations = gimme_number_generations(pool_size, Geqo_effort);
        status_interval = 10;
 
-/* seed random number generator */
-/* XXX why is this done every time around? */
-       if (Geqo_random_seed >= 0)
-               srandom((unsigned int) Geqo_random_seed);
-       else
-               srandom((unsigned int) time(NULL));
-
 /* allocate genetic pool memory */
        pool = alloc_pool(pool_size, number_of_rels);
 

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 2129042ed2538af7e97b631aaac97de706f9911a..709f3090d1a3e688cd8edc8c77f6c6262a3f7aab 100644 (file)
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.155 2003/09/04 05:11:20 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.156 2003/09/07 15:26:53 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -898,15 +898,6 @@ static struct config_int ConfigureNamesInt[] =
                &Geqo_generations,
                0, 0, INT_MAX, NULL, NULL
        },
-       {
-               {"geqo_random_seed", PGC_USERSET, QUERY_TUNING_GEQO,
-                       gettext_noop("Can be set to get reproducible results from the algorithm"),
-                       gettext_noop("If it is set to -1 then the algorithm behaves "
-                                                "non-deterministically")
-               },
-               &Geqo_random_seed,
-               -1, INT_MIN, INT_MAX, NULL, NULL
-       },
 
        {
                {"deadlock_timeout", PGC_SIGHUP, LOCK_MANAGEMENT,

diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index a30ae074a183c6d17735305963424024d422784f..c04aaab39bb7c7dc7fbe20c5513f94cbf47284a3 100644 (file)
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -121,7 +121,6 @@
 #geqo_generations = 0
 #geqo_pool_size = 0            # default based on tables in statement,
                                # range 128-1024
-#geqo_random_seed = -1         # -1 = use variable seed
 #geqo_selection_bias = 2.0     # range 1.5-2.0
 
 # - Other Planner Options -

diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index bcc52be98b73dc6fde1e7e1376503fd50c713dd1..f6174a73f2de1e7fbc6678c36b8f4ef26efae4f9 100644 (file)
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2000-2003, PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/tab-complete.c,v 1.84 2003/08/04 23:59:40 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/tab-complete.c,v 1.85 2003/09/07 15:26:54 tgl Exp $
  */
 
 /*----------------------------------------------------------------------
@@ -534,7 +534,6 @@ psql_completion(char *text, int start, int end)
                "geqo_effort",
                "geqo_generations",
                "geqo_pool_size",
-               "geqo_random_seed",
                "geqo_selection_bias",
                "geqo_threshold",
                "join_collapse_limit",

diff --git a/src/include/optimizer/geqo.h b/src/include/optimizer/geqo.h
index 0ead9dc304fd5cf5d2356dcb21d78e4c2b27ed9b..53a2334a1713d46effe91153268ec7e6d459eb6c 100644 (file)
--- a/src/include/optimizer/geqo.h
+++ b/src/include/optimizer/geqo.h
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: geqo.h,v 1.31 2003/08/04 02:40:13 momjian Exp $
+ * $Id: geqo.h,v 1.32 2003/09/07 15:26:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,8 +64,6 @@ extern double Geqo_selection_bias;
 #define MIN_GEQO_SELECTION_BIAS 1.5
 #define MAX_GEQO_SELECTION_BIAS 2.0
 
-extern int     Geqo_random_seed;       /* or negative to use current time */
-
 
 /* routines in geqo_main.c */
 extern RelOptInfo *geqo(Query *root, int number_of_rels, List *initial_rels);