RFR: Avoid superfluous proactive GCs

[Erik Österlund]

Hi Per,

Looks good.

/Erik

On 2018-01-08 15:58, Per Liden wrote:
> When running applications with a very small live-set and very low 
> allocation rate there's a tendency to do proactive GCs a little too 
> often. An idling jshell instance is an example of an application where 
> this can be seen, where we're doing GCs like every 5 second or so, 
> which is just annoying. With this patch we only consider doing 
> proactive GCs if the app has eaten some memory (at least 10%) or 
> enough time has passed (5 min).
>
> http://cr.openjdk.java.net/~pliden/zgc/avoid_superfluous_proactive_gcs/webrev.0/ 
>
>
> cheers,
> Per