pgpool2.git / summary / log / commit / refs

commit    89a647efd059d407cd1a4f3549f2b29798e45f98
Author:   Tatsuo Ishii <ishii@postgresql.org>
Date:     Wed May 17 08:35:43 2017 +0000

    Fix descriptions of white/black_memcache_table_list.
    
    They are far from actual implementations.
    See [pgpool-general: 5479] for more details.


 doc/src/sgml/memcache.sgml | 40 ++++++++++++++++++++++++++++++++--------
 1 file changed, 32 insertions(+), 8 deletions(-)

diff --git a/doc/src/sgml/memcache.sgml b/doc/src/sgml/memcache.sgml
index 2d98d316e..640f2a56e 100644
--- a/doc/src/sgml/memcache.sgml
+++ b/doc/src/sgml/memcache.sgml
@@ -20,6 +20,25 @@
     to <productname>PostgreSQL</productname> are involved, the serving
     of results from the in memory cache is extremely fast.
   </para>
+
+  <note>
+    <para>
+      Basically following SELECTs will not be cached:
+      <programlisting>
+	SELECTs including non immutable functions
+	SELECTs including temp tables, unlogged tables
+	SELECT result is too large (memqcache_maxcache)
+	SELECT FOR SHARE/UPDATE
+	SELECT starting with "/*NO QUERY CACHE*/" comment
+	SELECT including system catalogs
+	SELECT uses TABLESAMPLE
+      </programlisting>
+      However, VIEWs and SELECTs accessing unlogged tables can be
+      cached by specifying in
+      the <xref linkend="guc-white-memqcache-table-list">.
+    </para>
+  </note>
+
   <para>
     On the other hand, it might be slower than the normal path
     in some cases, because it adds some overhead to store cache.
@@ -211,8 +230,12 @@
 	<listitem>
 
 	  <para>
-	    Specifies a comma separated list of table names whose SELECT
-	    results should be cached by the <productname>Pgpool-II</productname>.
+	    Specifies a comma separated list of table names whose
+	    SELECT results should be cached by
+	    <productname>Pgpool-II</productname>.  This parameter only
+	    applies to VIEWs and SELECTs accessing unlogged tables.
+	    Regular tables can be cached unless specified
+	    by <xref linkend="guc-black-memqcache-table-list">.
 	  </para>
 
 	  <para>
@@ -237,12 +260,6 @@
 
 	    </para>
 	  </note>
-	  <note>
-	    <para>
-              <varname>white_memqcache_table_list</varname>
-              precedence over <xref linkend="guc-black-memqcache-table-list">
-	    </para>
-	  </note>
 	  <para>
 	    This parameter can be changed by reloading the <productname>Pgpool-II</productname> configurations.
 	  </para>
@@ -287,6 +304,13 @@
 	  <para>
 	    This parameter can be changed by reloading the <productname>Pgpool-II</productname> configurations.
 	  </para>
+	  <note>
+	    <para>
+              <varname>black_memqcache_table_list</varname>
+              precedence over <xref linkend="guc-white-memqcache-table-list">
+	    </para>
+	  </note>
+
 	</listitem>
       </varlistentry>
 


[parent: 4333d5a56eee]