Changeset 3811 for branches/2.4-stable/doc/src/docbook/admindoc/installation_upgrade.xml

Timestamp:

Oct 9, 2007, 2:15:16 PM (16 years ago)

Author:

Nicklas Nordborg

Message:

References #796: Don't create indexes on primary key columns for tables in the dynamic database

Added tool to remove indexes from dynamic db.

File:

• branches/2.4-stable/doc/src/docbook/admindoc/installation_upgrade.xml (modified) (1 diff)

branches/2.4-stable/doc/src/docbook/admindoc/installation_upgrade.xml

@@ -67 +67 @@
     <title>Upgrade instructions</title>
 
-    <important>
-      <title>Note to PostgreSQL users</title>
-      Upgrading BASE to versions earlier
-      than v2.2 is not be safe with an PostgreSQL database engine due
-      to a bug in Hibernate. The problem is reported to Hibernate
-      developers. There now exists a workaround for this problem. Read
-      more about the workaround on
-      the <ulink
-      url="http://base.thep.lu.se/wiki/UpgradePostgres">Upgrading a
-      Postgres database prior to BASE 2.2</ulink> page. This fix is
-      not needed for the release which this document is a part of.
+    <important id="dropindexes">
+      <title>Upgrading from BASE 2.4.3 or lower to 2.4.4 or higher</title>
+      <para>
+        Older releases of BASE 2 used to create indexes for many columns
+        in the dynamic database. The same columns are part of the primary
+        key for the tables so the indexes are not really needed. The 
+        result is very bad performance since the database engine sometimes 
+        get stuck in "index update" mode making the entire server
+        very slow. BASE 2.4.4 no longer creates the indexes. Indexes on
+        existing tables should be dropped to increase the performance.
+        Tests have shown a 50-90% decrease in execution time for some 
+        plug-ins
+        (<ulink url="http://base.thep.lu.se/ticket/294">http://base.thep.lu.se/ticket/294</ulink>). 
+      </para>
+      <para>
+        Removing the indexes is very simple. <emphasis>After the server
+        has been upgraded</emphasis> following the usual instructions below, issue the
+        the following commands:
+      </para>
+    
+      <programlisting>
+cd &lt;basedir&gt;/bin
+./dynamicdb.sh -v -dropindexes
+</programlisting>
+
+      <para>
+        Skip the <option>-dropindexes</option> option to do a dry
+        run without actually deleting the indexes.
+      </para>
     </important>