svn commit - mysqldoc@docsrva: r14881 - in trunk: . refman-5.4

[paul.dubois]

Author: paul
Date: 2009-05-12 05:12:15 +0200 (Tue, 12 May 2009)
New Revision: 14881

Log:
 r41098@frost:  paul | 2009-05-11 22:10:10 -0500
 innodb_thread_concurrency_timer_based requires innodb_thread_concurrency > 0


Modified:
   trunk/refman-5.4/introduction.xml
   trunk/refman-5.4/se-innodb-core.xml

Property changes on: trunk
___________________________________________________________________
Name: svk:merge
   - 4767c598-dc10-0410-bea0-d01b485662eb:/mysqldoc-local/mysqldoc/trunk:41755
7d8d2c4e-af1d-0410-ab9f-b038ce55645b:/mysqldoc-local/mysqldoc:41093
b5ec3a16-e900-0410-9ad2-d183a3acac99:/mysqldoc-local/mysqldoc/trunk:14218
bf112a9c-6c03-0410-a055-ad865cd57414:/mysqldoc-local/mysqldoc/trunk:38062
   + 4767c598-dc10-0410-bea0-d01b485662eb:/mysqldoc-local/mysqldoc/trunk:41755
7d8d2c4e-af1d-0410-ab9f-b038ce55645b:/mysqldoc-local/mysqldoc:41098
b5ec3a16-e900-0410-9ad2-d183a3acac99:/mysqldoc-local/mysqldoc/trunk:14218
bf112a9c-6c03-0410-a055-ad865cd57414:/mysqldoc-local/mysqldoc/trunk:38062


Modified: trunk/refman-5.4/introduction.xml
===================================================================
--- trunk/refman-5.4/introduction.xml	2009-05-12 02:52:28 UTC (rev 14880)
+++ trunk/refman-5.4/introduction.xml	2009-05-12 03:12:15 UTC (rev 14881)
Changed blocks: 2, Lines Added: 36, Lines Deleted: 4; 2548 bytes

@@ -546,7 +546,11 @@
           <literal role="statvar">Innodb_have_sync_atomic</literal> is
           <literal>OFF</literal>, enabling
           <literal role="sysvar">innodb_thread_concurrency_timer_based</literal>
-          has no effect.
+          has no effect. The lock-free concurrency method also requires
+          that
+          <literal role="sysvar">innodb_thread_concurrency</literal> be
+          set to a value greater than 0 (the default value in
+          &current-series;).
         </para>
 
         <para>

@@ -1026,10 +1030,38 @@
               <literal role="sysvar">innodb_thread_concurrency_timer_based</literal>:
               If enabled, use a lock-free timer-based method of handling
               thread concurrency. If disabled, the original mutex-based
-              method is used. The lock-free concurrency method depends
-              on the availability of atomic instructions, so if the
+              method is used. For the lock-free concurrency method to be
+              used, two requirements must be satisfied:
+            </para>
+
+            <itemizedlist>
+
+              <listitem>
+                <para>
+                  The <literal>innodb_thread_concurrency</literal>
+                  system variable must be set to a number greater than
+                  0. The default value in MySQL &current-series; is 0,
+                  so you must change it to use the lock-free concurrency
+                  method.
+                </para>
+              </listitem>
+
+              <listitem>
+                <para>
+                  Atomic instructions must be available. That is, the
+                  <literal role="statvar">Innodb_have_sync_atomic</literal>
+                  status variable must be <literal>ON</literal>.
+                </para>
+              </listitem>
+
+            </itemizedlist>
+
+            <para>
+              If
+              <literal role="sysvar">innodb_thread_concurrency</literal>
+              is 0 or
               <literal role="statvar">Innodb_have_sync_atomic</literal>
-              status variable is <literal>OFF</literal>, enabling
+              is <literal>OFF</literal>, enabling
               <literal role="sysvar">innodb_thread_concurrency_timer_based</literal>
               has no effect.
             </para>


Modified: trunk/refman-5.4/se-innodb-core.xml
===================================================================
--- trunk/refman-5.4/se-innodb-core.xml	2009-05-12 02:52:28 UTC (rev 14880)
+++ trunk/refman-5.4/se-innodb-core.xml	2009-05-12 03:12:15 UTC (rev 14881)
Changed blocks: 1, Lines Added: 31, Lines Deleted: 5; 1917 bytes

@@ -2402,11 +2402,37 @@
         <para>
           If this variable is enabled, use a lock-free timer-based
           method of handling thread concurrency. If disabled, the
-          original mutex-based method is used. The new concurrency
-          method depends on the availability of atomic instructions, so
-          if the
-          <literal role="statvar">Innodb_have_sync_atomic</literal>
-          status variable is <literal>OFF</literal>, enabling
+          original mutex-based method is used. For the lock-free
+          concurrency method to be used, two requirements must be
+          satisfied:
+        </para>
+
+        <itemizedlist>
+
+          <listitem>
+            <para>
+              The <literal>innodb_thread_concurrency</literal> system
+              variable must be set to a number greater than 0. The
+              default value in MySQL &current-series; is 0, so you must
+              change it to use the lock-free concurrency method.
+            </para>
+          </listitem>
+
+          <listitem>
+            <para>
+              Atomic instructions must be available. That is, the
+              <literal role="statvar">Innodb_have_sync_atomic</literal>
+              status variable must be <literal>ON</literal>.
+            </para>
+          </listitem>
+
+        </itemizedlist>
+
+        <para>
+          If <literal role="sysvar">innodb_thread_concurrency</literal>
+          is 0 or
+          <literal role="statvar">Innodb_have_sync_atomic</literal> is
+          <literal>OFF</literal>, enabling
           <literal role="sysvar">innodb_thread_concurrency_timer_based</literal>
           has no effect.
         </para>