RFR: 8221153: ZGC: Heap iteration and verification pollutes GC statistics

[Erik Österlund]

Hi Per,

Looks good.

Thanks,
/Erik

On 2019-03-27 22:54, Per Liden wrote:
> When performing heap iteration and verification we should disable 
> ZStatTimers to avoid polluting the GC statistics. This can otherwise 
> look very odd in GC logs, with statistics that is hard to interpret 
> since the times recorded doesn't come from a GC pause.
>
> This patch introduces ZStatTimerDisable, which can be placed in scopes 
> where we want ZStatTimers to be disabled.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8221153
> Webrev: http://cr.openjdk.java.net/~pliden/8221153/webrev.0
>
> /Per