fastdebug, taskset -c 0, -XX:ShenandoahGCHeuristics=aggressive, Terminator assert

[Aleksey Shipilev]

Run like this (note that no class/jar is supplied, bootstrap crashes):

$ taskset -c 0
~/trunks/shenandoah-jdk9/build/linux-x86_64-normal-server-fastdebug/images/jdk//bin/java
-Xlog  -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive

Crashes like below, probably because reference processing restarts the
task with the same terminator. Should probably do what G1 is doing with
sequential ref processing.

[0.161s][info][gc,phases,start  ] Pause Init-Evacuation (0.161s)
[0.161s][info][gc,task          ] GC Workers: using 1 out of 1
[0.161s][info][gc,task          ] GC Workers: using 1 out of 1
[0.161s][info][gc,task          ] GC Workers: using 1 out of 1
[0.161s][info][gc,task          ] ENTER:
ShenandoahConcurrentMark::final_mark_loop thread 0x00007f6184048800
terminator 0x00007f61891dc780
[0.161s][info][gc,task          ] ENTER: offer_termination() thread
0x00007f6184048800, offered=0
[0.161s][info][gc,task          ] EXIT TRUE: offer_termination() thread
0x00007f6184048800, offered=1
[0.161s][info][gc,task          ] EXITING:
ShenandoahConcurrentMark::final_mark_loop thread 0x00007f6184048800
terminator 0x00007f61891dc780
[0.161s][info][gc,task          ] GC Workers: using 1 out of 1
[0.161s][info][gc,task          ] ENTER:
ShenandoahConcurrentMark::final_mark_loop thread 0x00007f61841aa000
terminator 0x00007f61891dc6e0
[0.161s][info][gc,task          ] ENTER: offer_termination() thread
0x00007f61841aa000, offered=0
[0.161s][info][gc,task          ] EXIT TRUE: offer_termination() thread
0x00007f61841aa000, offered=1
[0.161s][info][gc,task          ] EXITING:
ShenandoahConcurrentMark::final_mark_loop thread 0x00007f61841aa000
terminator 0x00007f61891dc6e0
[0.161s][info][gc,task          ] ENTER:
ShenandoahConcurrentMark::final_mark_loop thread 0x00007f61841aa000
terminator 0x00007f61891dc6e0
[0.161s][info][gc,task          ] ENTER: offer_termination() thread
0x00007f61841aa000, offered=1
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc:  SuppressErrorAt=/taskqueue.cpp:157
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error
(/home/shade/trunks/shenandoah-jdk9/hotspot/src/share/vm/gc/shared/taskqueue.cpp:157),
pid=28073, tid=28078
#  assert(_offered_termination < _n_threads) failed: Invariant
#
# JRE version: OpenJDK Runtime Environment (9.0) (fastdebug build
9-internal+0-2016-09-21-132926.shade.shenandoah-jdk9)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug
9-internal+0-2016-09-21-132926.shade.shenandoah-jdk9, mixed mode,
tiered, compressed oops, Shenandoah gc, linux-amd64)
# Core dump will be written. Default location: Core dumps may be
processed with "/usr/share/apport/apport %p %s %c %P" (or dumping to
/home/shade/projects/jol/core.28073)
#
# An error report file with more information is saved as:
# /home/shade/projects/jol/hs_err_pid28073.log
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.java.com/bugreport/crash.jsp
#

Thanks,
-Aleksey