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<tt>Hi Jon,</tt><br>
<br>
<div class="moz-cite-prefix">On 2016-05-27 07:46, Jon Masamitsu
wrote:<br>
</div>
<blockquote
cite="mid:cef5236e-31b9-0c05-f859-b58619f0ef88@oracle.com"
type="cite">
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<a moz-do-not-send="true" class="moz-txt-link-freetext"
href="https://bugs.openjdk.java.net/browse/JDK-8026752">https://bugs.openjdk.java.net/browse/JDK-8026752</a><br>
<br>
If a concurrent CMS collection has been scheduled for Metaspace<br>
needs, it should be cancelled if a full GC is done.<br>
<br>
<a moz-do-not-send="true" class="moz-txt-link-freetext"
href="http://cr.openjdk.java.net/%7Ejmasa/8026752/webrev.00/">http://cr.openjdk.java.net/~jmasa/8026752/webrev.00/</a><br>
<br>
Fix was verified with the new test TestMetaspaceCMSCancel.java<br>
Stability testing was done with gc_test_suite.<br>
<br>
</blockquote>
<tt>I think the fix is good. Just one question regarding where to do
the call. Is there a reason that you have put
MetaspaceGC::set_should_concurrent_collect(false) in
reset_after_compaction()? To me it would make more sense to have
the call in CMSCollector::do_compaction_work(...).</tt><tt><br>
</tt><tt><br>
</tt><tt>Regarding the test, I think it is a bit unfortunate to have
to sleep for 20s to verify this, especially since there have been
efforts to shorten the test-time. What do you think about adding a
WhiteBox-method for checking the value of
MetaspaceGC::_should_concurrent_collect and have the test be
something like:</tt><tt><br>
</tt><tt>assertTrue(WB.metaspaceShouldConcurrentCollect());</tt><tt><br>
</tt><tt>System.gc();</tt><tt><br>
</tt><tt>assertFalse(WB.metaspaceShouldConcurrentCollect());</tt><tt><br>
</tt><tt><br>
</tt><tt>Doing this you should be able to avoid using the process
builder as well.</tt><tt><br>
</tt><tt><br>
</tt><tt>Thanks,</tt><tt><br>
</tt><tt>Stefan</tt><br>
<blockquote
cite="mid:cef5236e-31b9-0c05-f859-b58619f0ef88@oracle.com"
type="cite"> Thanks.<br>
<br>
Jon<br>
</blockquote>
<br>
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