Crash in openjdk8 while using ShenandoahGC

[Peter Beaman]

Our Java application running on an AWS r3.xlarge instance under Ubuntu
14.04 crashed with the following after about 12 hours of fairly CPU- and
GC-intense processing:

#  Internal Error (safepoint.cpp:314), pid=3384, tid=0x00007f7448f77700
#  guarantee(PageArmed == 0) failed: invariant
#
# JRE version: OpenJDK Runtime Environment (8.0_141) (build
1.8.0_141-internal-15)
# Java VM: OpenJDK 64-Bit Server VM (25.141-b15 mixed mode linux-amd64
compressed oops)

The complete hs_err and gc.log files are available if useful. Unfortunately
the machine was not equipped with enough storage to hold a crashdump file.
I have not yet reproduced this, so do not yet know how easy or hard that
may be.

The JVM was built from source at tag jdk8u141-b15,

JVM flags from gc.log:

OpenJDK 64-Bit Server VM (25.141-b15) for linux-amd64 JRE
(1.8.0_141-internal-15), built on Aug 30 2017 20:07:13 by "pbeaman" with
gcc 4.8.4
Memory: 4k page, physical 31399920k(29785452k free), swap 0k(0k free)
CommandLine flags: -XX:InitialHeapSize=22506635264
-XX:MaxHeapSize=22506635264 -XX:MaxMetaspaceSize=201326592
-XX:NumberOfGCLogFiles=10 -XX:-OmitStackTraceInFastThrow
-XX:OnOutOfMemoryError=touch /opt/bti/OUT_OF_MEMORY
-XX:+PrintAdaptiveSizePolicy -XX:+PrintGC
-XX:+PrintGCApplicationStoppedTime -XX:+PrintGCDateStamps
-XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintTenuringDistribution
-XX:+UseCompressedClassPointers -XX:+UseCompressedOops
-XX:-UseGCLogFileRotation -XX:+UseShenandoahGC -XX:+UseStringDeduplication

We are testing Shenandoah as a possible cure for long Full GC stop times in
G1.

Please let me know if there's a preferred channel for filing Shenandoah
bugs.

Thanks,

Peter Beaman
Onshape