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<p>On 11/3/17 6:05 AM, Vitaly Davidovich wrote:<br>
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cite="mid:CAHjP37Er=aXdcM0K87wP8G9Vpo4tPtXYCRkxKASMZhs0LZ0dmQ@mail.gmail.com">
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<div dir="auto">On Thu, Nov 2, 2017 at 10:03 PM <<a
href="mailto:dean.long@oracle.com" moz-do-not-send="true">dean.long@oracle.com</a>>
wrote:<br>
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<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"> From a
quick search, this sounds similar to 8085965. I wonder if<br>
another circularity in the siblings list has been created
somehow. Can<br>
you check for that with gdb?</blockquote>
<div dir="auto">Hi Dean,</div>
<div dir="auto"><br>
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<div dir="auto">Yes it does sound like that bug, although
that’s marked as fixed in 8u72. I guess the implication is
that it’s not actually fixed or this is a different
codepath/circumstance that ends up in the same blackhole.</div>
<div dir="auto"><br>
</div>
<div dir="auto">I’ll see if my colleagues can dig around in
the core file. It’s a product build so not sure how easy it
will be to make sense of it without debug symbols.</div>
<div dir="auto"><br>
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<br>
I'm not an expert with jhsdb/clhsdb/hsdb, but I believe it can
attach to a core file and give you some information even with a
product build.<br>
<br>
dl<br>
<br>
<blockquote type="cite"
cite="mid:CAHjP37Er=aXdcM0K87wP8G9Vpo4tPtXYCRkxKASMZhs0LZ0dmQ@mail.gmail.com">
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<div dir="auto">Thanks</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
<br>
dl<br>
<br>
<br>
On 10/31/17 11:08 AM, Vitaly Davidovich wrote:<br>
> Hi guys,<br>
><br>
> I have some colleagues who appear to be running into<br>
> <a
href="https://bugs.openjdk.java.net/browse/JDK-8059128"
rel="noreferrer" target="_blank" moz-do-not-send="true">https://bugs.openjdk.java.net/browse/JDK-8059128</a>
on Oracle JDK 8u144<br>
> (Linux, x86-64). Naturally, there's no reproducer but
they've seen<br>
> this happen several times in the last couple of months.<br>
><br>
> The symptom is the JVM becomes unresponsive - the
application is not<br>
> servicing any traffic, and jstack doesn't work without
the force<br>
> option. jstack output (with native frames) captured
some time apart<br>
> shows the compiler thread either in
Parse::do_all_blocks -><br>
> do_one_block -> do_one_bytecode -> ...<br>
> InstanceKlass::has_finalizable_subclass -><br>
> Dependencies::find_finalizable_subclass or <same as
the previous one><br>
> ... Dependencies::has_finalizable_subclass() ->
Klass::next_sibling()<br>
><br>
> I see that 8059128 was closed as Incomplete, but it
does look like<br>
> there's a real issue here. Has anyone looked into this
further or has<br>
> any new thoughts/ideas?<br>
><br>
> My understanding is the working theory is it's related
to some data<br>
> race between class unloading and the compiler thread
observing an<br>
> inconsistent (corrupt?) type hierarchy. I see<br>
> <a
href="https://bugs.openjdk.java.net/browse/JDK-8114823"
rel="noreferrer" target="_blank" moz-do-not-send="true">https://bugs.openjdk.java.net/browse/JDK-8114823</a>
is also noted as<br>
> possibly related - the app we're having trouble with is
using G1, but<br>
> class unloading isn't disabled of course. Is there
some work around<br>
> to reduce the likelihood of having the compiler thread
and GC cross<br>
> paths like this?<br>
><br>
> Let me know if you need more info.<br>
><br>
> Thanks<br>
<br>
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<div dir="ltr">-- <br>
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<div class="gmail_signature" data-smartmail="gmail_signature">Sent
from my phone</div>
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