SIGSEGV on PhaseIdealLoop::split_up?

[Dawid Weiss]

Hi guys,

Let me reply to both e-mails at once.

> A reproducer would be very nice. Did you try to reproduce with Replay Compilation?

I haven't tried to reproduce it, but it's popping up quite a bit
recently, see here for a backlog:

https://lucene.markmail.org/search/%22jenkins+server%22+PhaseIdealLoop::split_up+list:org.apache.lucene.java-dev+order:date-backward

For example this one
https://jenkins.thetaphi.de/job/Lucene-Solr-7.x-Linux/3472/

is:

  [junit4] # JRE version: OpenJDK Runtime Environment (11.0+28) (build 11+28)
  [junit4] # Java VM: OpenJDK 64-Bit Server VM (11+28, mixed mode,
tiered, g1 gc, linux-amd64)

Some of those builds are still on the server (and contain hs logs).
What worries me is that this only happens on Uwe's machine -- may be
related to particular hardware config it happens on.

A repro isn't going to be easy (are they ever? ;) as those tests run
pretty much at random within a single forked JVM and I bet it's just
some unusual pattern that tiggers the problem. Looking at where the
problem occurs it seems there is a common core related to compiling
this method:

Current CompileTask:
C2:1534619 50541  s!   4
org.apache.lucene.index.ConcurrentMergeScheduler::merge (280 bytes)

The path leading to it may differ (when you diff those different
hs_err logs against each other), but it seems to be caused by merge
compilation in all cases I looked at.

I can monitor this and attach new logs to the Jira issue
(LUCENE-8668). Uwe will be at Fosdem so I'm sure he'll be ready to
figure it out together with you, should you be there.

Dawid


On Wed, Jan 30, 2019 at 11:22 AM Nils Eliasson <nils.eliasson at oracle.com> wrote:
>
> Sorry, too fast. You had already tested on various builds.
>
> Regards,
>
> Nils
>
> On 2019-01-30 10:57, Nils Eliasson wrote:
> > Hi Dawid,
> >
> > The hs_err-file is from a JDK 10 build. Would you mind testing with
> > JDK 11 or JDK 12-ea?
> >
> > What build of Lucene was this run against? Can point me to the
> > relevant jar? I will try reproducing with 7.6.0.
> >
> > Regards,
> >
> > Nils
> >
> > On 2019-01-30 10:27, Dawid Weiss wrote:
> >> Hello,
> >>
> >> There's quite a few of those JVM errors that popped up recently on one
> >> of Lucene's CI machines:
> >>
> >> https://issues.apache.org/jira/browse/LUCENE-8668
> >>
> >> Happens on various JVMs (see the above issue). Would it be something
> >> familiar to any of you? A known issue or should we try to keep digging
> >> (for a repro, for example)?
> >>
> >> Dawid