Increase default value of effective_cache_size to 128MB, per discussion.

This commit is contained in:
Tom Lane 2006-09-25 22:12:24 +00:00
parent ffae5cc5a6
commit 0f8fc35a5a
3 changed files with 8 additions and 8 deletions

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@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.88 2006/09/18 12:11:36 teodor Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.89 2006/09/25 22:12:24 tgl Exp $ -->
<chapter Id="runtime-config">
<title>Server Configuration</title>
@ -1905,7 +1905,7 @@ archive_command = 'copy "%p" /mnt/server/archivedir/"%f"' # Windows
<listitem>
<para>
Sets the planner's assumption about the effective size of the
disk cache that is available to a single index scan. This is
disk cache that is available to a single query. This is
factored into estimates of the cost of using an index; a
higher value makes it more likely index scans will be used, a
lower value makes it more likely sequential scans will be
@ -1913,13 +1913,13 @@ archive_command = 'copy "%p" /mnt/server/archivedir/"%f"' # Windows
<productname>PostgreSQL</productname>'s shared buffers and the
portion of the kernel's disk cache that will be used for
<productname>PostgreSQL</productname> data files. Also, take
into account the expected number of concurrent queries using
different indexes, since they will have to share the available
into account the expected number of concurrent queries on different
tables, since they will have to share the available
space. This parameter has no effect on the size of shared
memory allocated by <productname>PostgreSQL</productname>, nor
does it reserve kernel disk cache; it is used only for
estimation purposes. The value is measured in disk pages,
which are normally 8192 bytes each. The default is 1000.
which are normally 8192 bytes each. The default is 16384 (128 MB).
</para>
</listitem>
</varlistentry>

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@ -195,7 +195,7 @@
#cpu_tuple_cost = 0.01 # same scale as above
#cpu_index_tuple_cost = 0.005 # same scale as above
#cpu_operator_cost = 0.0025 # same scale as above
#effective_cache_size = 8000kB
#effective_cache_size = 128MB
# - Genetic Query Optimizer -

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@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.80 2006/09/19 22:49:53 tgl Exp $
* $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.81 2006/09/25 22:12:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -27,7 +27,7 @@
#define DEFAULT_CPU_INDEX_TUPLE_COST 0.005
#define DEFAULT_CPU_OPERATOR_COST 0.0025
#define DEFAULT_EFFECTIVE_CACHE_SIZE 1000 /* measured in pages */
#define DEFAULT_EFFECTIVE_CACHE_SIZE 16384 /* measured in pages */
/*