RFR: ZGC: Concurrent StringTable

[Robbin Ehn]

Forgot to mention this goes on-top of:
8195097: Make it possible to process StringTable outside safepoint
http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2018-May/028209.html

Not yet in jdk/jdk.

Thanks, Robbin

On 05/28/2018 06:23 PM, Robbin Ehn wrote:
> Hi, please review.
> 
> This change-set updates ZGC to walk stringtable concurrently by default.
> 
> Disable with: -XX:-ZConcurrentStringTable
> 
> Note that we don't support cleaning via ServiceThread.
> 
> Webrev: http://cr.openjdk.java.net/~rehn/zgc-concurrent-stringtable/v0/webrev/
> 
> Thanks, Robbin