RER: Parallel object monitor scanning

[Roman Kennke]

Hi Zhengyu,

just got this when running SPECjvm2008 with
-XX:ShenandoahGCHeuristics=aggressive:

#  Internal Error (/home/rkennke/src/openjdk/jdk9-
shenandoah/hotspot/src/share/vm/runtime/synchronizer.cpp:1939),
pid=19893, tid=19913
#  assert(block->object() == (cast_to_oop<intptr_t>(-2))) failed: Must
be a claimed block

coming from:
V  [libjvm.so+0xa2a380]  report_vm_error(char const*, int, char const*,
char const*, ...)+0xe0
V  [libjvm.so+0x152461c]  ParallelObjectSynchronizerIterator::~Parallel
ObjectSynchronizerIterator()+0xcc

Roman

Am Mittwoch, den 23.11.2016, 13:33 -0500 schrieb Zhengyu Gu:
> Hi,
> 
> I have been holding this patch for a while, since I could not get
> definitive measurement.
> 
> Thanks for Aleksey's new benchmark, it shows 50+% improvement.
> 
> 
> Webrev: http://cr.openjdk.java.net/~zgu/shenandoah/par-om/webrev.00/i
> ndex.html
> 
> Without patch: http://cr.openjdk.java.net/~zgu/shenandoah/par-om/with
> out-patch.txt
> With patch:    http://cr.openjdk.java.net/~zgu/shenandoah/par-om/with
> -patch.txt
> 
> Thanks,
> 
> -Zhengyu
>