Changeset 13542

Timestamp:

08/28/11 07:46:16 (10 years ago)

Author:

Mark Evenson

Message:

Include instructions for what to do about PermGen? memory errors.

Note that bugs may now be submitted via OpenID authentication to the
common-lisp.net infrastructure.

File:

• public_html/faq.shtml (modified) (10 diffs)

public_html/faq.shtml

@@ -37 +37 @@
   </li> 
 
+  <li><a href="#running">Running</a>
+  <ol>
+    <li><a href="#maxpermgen-errors">Java is running out of memory an error reporting something about "java.lang.OutOfMemoryError: PermGen space".  What can I do?</a></li>
+  </ol>
+  </li> 
 </ol>
 
@@ -56 +61 @@
 contributions in this area would be greatly appreciated, of course.
 </p>
-
 </div>
 
@@ -86 +90 @@
 if you distribute ABCL, but otherwise the license of ABCL is not viral.
 </p>
-
 </div>
 
@@ -93 +96 @@
 
 <p>
-
 The current state of issues can be found in the <a
 href="http://trac.common-lisp.net/armedbear/report/1">ABCL issue
-tracker</a>.  Unfortunately, due to spamming problems, administration
-of bugs has been closed for anybody but common-lisp.net members.</p>
-
-<p>
-
-To report a bug, please mail a description of the problem, the version
-of ABCL you are using, and if possible a set of steps to reproduce the
-problem to the <a
+tracker</a>.  Individuals with an <a
+href="http://en.wikipedia.org/wiki/Openid">OpenID</a> such as a Google
+ID may enter information directly in the bug tracker after
+authenticating by your provider. </p>
+
+<p>
+
+Alternatively, to report a bug, please mail a description of the
+problem, the version of ABCL you are using, and if possible a set of
+steps to reproduce the problem to the <a
 href="http://common-lisp.net/cgi-bin/mailman/listinfo/armedbear-devel">armedbear-devel
 mailing list</a>.  We try to respond within a day at most to messages.
@@ -139 +143 @@
 plenty of room for improvement in the area of execution speed and optimization.
 The project welcomes initiatives to improve performance.</p>
-
 </div>
 
@@ -165 +168 @@
   improve this measure too.</p>
 
-<p>ABCL 0.26.1 fails roughly 20 out of 21702 tests in the ANSI test
+<p>ABCL 0.26.2 fails roughly 20 out of 21702 tests in the ANSI test
 suite in interpreted and compiled modes, a constant number over the
-past releases.  Most failures relate to pretty printing.</p>
+past releases.</p>
 
 <p>As a measure of 'improvement achieved', the development team refers
@@ -174 +177 @@
   'only' ca 75 failing tests at the time of 0.15.0, and even 1400 failures
   around October 2008.</p>
-
 </div>
 
@@ -188 +190 @@
 <a href="http://svn.common-lisp.net/armedbear/trunk/abcl">http://svn.common-lisp.net/armedbear/trunk/abcl</a>
 </p>
-
-
 </div>
 
@@ -205 +205 @@
 href="http://trac.common-lisp.net/armedbear/browser/trunk/abcl/examples">examples</a></li>
 </ol>
-
-</div>
+</div>
+
 </div>
 
@@ -223 +223 @@
 the <code>abcl.build.incremental</code> property.
 </p>
-
-</div>
-</div>
+</div>
+
+</div>
+
+<div class="h2" title="Running" id="running">
+<h2>Running</h2>
+
+<div class="h3" title="Out of Memory errors" id="maxpermgen-errors">
+<h3>Java is running out of memory an error reporting something about "java.lang.OutOfMemoryError: PermGen space".  What can I do?</h3>
+
+<p>
+  You need to increase the memory which the Java allocates for
+  permanent generation ("PermGen)" objects by using the appropiate
+  switch on command line which invokes the JVM hosting ABCL.  When the
+  implementation compiles or loads Lisp code, it creates a separate
+  JVM class for each top-level form.  With large workloads, this can
+  overrun the part of memory which Java reserves for storing the class
+  definition which results in the error you are seeing.
+</p>
+
+<p>
+  The exact manner of configuring this option which unfortunately
+  varies by implementation.  For the Oracle HotSpot 64bit JVM,
+  something like <code>"-d64 -Xmx4g -XX:MaxPermSize=1g
+  -XX:+CMSClassUnloadingEnabled"</code> will not only increse the
+  PermGen space, but will ensure you always invoke the 64bit JVM,
+  increase the maximum memory space available to the JVM to 4Gib, and
+  allow the JVM to garbage collect class definitions which its deems
+  to be unused.
+</p>
+
+<p>
+  If you are compiling ABCL from source, a handy way to have the build
+  process incorporate such runtime flags in the JVM invocation would
+  be to copy the <code>'abcl.properties.in'</code> file to <code>'abcl.properties'</code>, and
+  then ensure that the <code>'java.options'</code> variable is set to the desired
+  options.
+</p>
+</div>
+
+</div>
+
 </div>