[8] RFR: Shenandoah: JNI weak roots are always cleared before Full GC mark

[Zhengyu Gu]

Looks good.

-Zhengyu

On 6/22/20 1:39 PM, Aleksey Shipilev wrote:
> Amir found the crash with Cassandra that started to happen recently with Shenandoah 8u. It
> reproduces more or less reliably with starting Cassandra 3.11.4 with fastdebug build and
> -XX:ShenandoahGCMode=passive -XX:-ShenandoahDegeneratedGC.
> 
> This is a symptom of a larger problem (see JDK-8248041), but 8u it is catastrophic due to clearing
> of the weak roots.
> 
> Fix:
>    https://cr.openjdk.java.net/~shade/shenandoah/8u-fullgc-jni-weak/webrev.01/
> 
> Testing: hotspot_gc_shenandoah; Cassandra tests
>