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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">the VM currently starts a large amount of GC threads on systems with many CPUs regardless of the Java heap size.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This doesn't make sense for very small heap sizes.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The number of ParallelGCThreads can be observed by e.g.:<o:p></o:p></span></p>
<p class="MsoNormal">jdk/bin/java -Xmx128m -XX:+PrintFlagsFinal -version|grep GCThreads<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">My proposal is to use up to 1 GC thread per 64 MB of heap:<o:p></o:p></span></p>
<p class="MsoNormal"><a href="http://cr.openjdk.java.net/~mdoerr/8198510_gc_threads/webrev.00/">http://cr.openjdk.java.net/~mdoerr/8198510_gc_threads/webrev.00/</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Please review.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Martin<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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