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<div class="moz-forward-container">Hi all,<br>
<br>
<br>
in a Java heap dump of 7u21 we can see accumulating tons of GC
related diagnostics message strings.<br>
This will result in an OOME finally. These millions of strings are
e.g.:<br>
<br>
"end of minor GC", <span id="form1:panelPage1">"end of major
GC", "Copy", "Allocation Failure", </span>"PS Scavenge"<br>
<br>
Interestingly these stings are root objects and are never been
collected. What is<br>
the purpose of these messages? Are they supposed to go into a
logfile?<br>
We didn't see them anywhere.<br>
<br>
And what JVM flag needs to be enabled to trigger their creation?<br>
<br>
From memoryManager.cpp<br>
<br>
if (<b>is_notification_enabled()</b>) {<br>
320 bool isMajorGC = this ==
MemoryService::get_major_gc_manager();<br>
321 GCNotifier::pushNotification(this, isMajorGC ? "end
of major GC" : "end of minor GC",<br>
322
GCCause::to_string(cause));<br>
<br>
<br>
In other words, how can we set the boolean _notification_enabled
to false in order to suppress<br>
the creation of these annoying strings?<br>
<br>
Further on I'm wondering why these strings are being created in
Java heap rather than as internal strings<br>
in perm in order to avoid millions of duplicates.<br>
<br>
Right now I consider this a bug which is btw not reproducible with
JRockit and also not reproducible<br>
with Java SE 6. Only 7.<br>
<br>
<br>
Thanks and Regards<br>
<br>
Thomas <br>
<br>
<br>
<br>
<br>
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