jdk8u backport is brokent in 1.8.0.232.b09

[Roman Kennke]

I just realized that in your latest test you used a Zero VM. This is
most likely not what you wanted ;-)

Please try:

Release build:
https://builds.shipilev.net/openjdk-shenandoah-jdk8/openjdk-shenandoah-jdk8-latest-linux-aarch64-release.tar.xz

Fastdebug build:
https://builds.shipilev.net/openjdk-shenandoah-jdk8/openjdk-shenandoah-jdk8-latest-linux-aarch64-fastdebug.tar.xz

Thanks,
Roman


> Hello, Shenandoah devs.
> I updated jdk8 from 191-b12 to 232-b09 and started to get spurious freezes
> of my application during startup which occur pretty consistently. Digging
> into gave me impression that is something wrong with java itself. Having
> tried to use fastdebug build I started to get these hs_err.logs:
> https://gist.github.com/genuss/e1969c081f7656ea14e992d84dc8a180
> https://gist.github.com/genuss/310b67fc3f1f49b458c0e13f13b67fdd
> and another possible outcome is same as earlier - hung jvm which heavily
> consumes CPU in GC threads with a stacktrace like that (got it with perf):
> 32.32%  libjvm.so     [.] ShenandoahAsserts::assert_correct
> 16.16%  libjvm.so     [.] ShenandoahBarrierSet::write_barrier
> 10.10%  libjvm.so     [.] JvmtiTagMap::do_weak_oops
> 8.43%  libjvm.so      [.] ShenandoahForwardedIsAliveClosure::do_object_b
> 8.25%  libjvm.so      [.]
> ShenandoahEvacuateUpdateRootsClosure::do_oop_work<oop>
> 6.71%  libjvm.so      [.] ShenandoahHeap::in_collection_set<oop>
> 6.16%  libjvm.so      [.] ShenandoahHeap::is_in
> 5.53%  libjvm.so      [.] Metaspace::contains
> 2.70%  libjvm.so      [.] ShenandoahHeap::heap
> 2.43%  libjvm.so      [.] ShenandoahHeap::kind
> 0.76%  libjvm.so      [.] ShenandoahHeap::heap_no_check
> 0.24%  [kernel]       [k] trigger_load_balance
> 0.14%  [kernel]       [k] system_call_fastpath
> 
> Aleksey Shipilev suggested running on latest shenandoah-backport. I did it
> and it gave me another error in 100% cases (probably unrelated to original
> error). The log is here
> https://gist.github.com/genuss/10eae7f6cc41e9ea1c59ca723915353b
> 
> Moving back to 1.8.0.192 helps, but maybe we can find the error here.
> Unfortunately I don't haven a minimal reproducible example, but I'm open to
> any suggestions on how to make it.
> Do you have any thoughts about how to fix this?
> 
> Alexey
>