ZGC cpu metrics in logs

[Sundara Mohan M]

Ok, thanks for the clarification.

On Thu, Oct 24, 2019 at 12:57 AM Per Liden <per.liden at oracle.com> wrote:

> Hi,
>
> On 10/24/19 2:49 AM, Sundara Mohan M wrote:
> > Hi,
> >      Wondering why zgc doesn't print cpu metrics like below
> >
> > [2019-10-23T17:42:48.539+0800][0.959s][info][gc,cpu      ] GC(118)
> > User=0.00s Sys=0.00s Real=0.00s
> >
> > For any other garbage collectors it is printed.
> > Is this avoid because ZGC stop the world pause is always in milliseconds?
> >
> > Just curious why this was not printed for ZGC alone.
>
> Right, printing that exact line wouldn't be that useful, as ZGC pauses
> wouldn't normally register on that scale.
>
> However, printing more detailed timing information could certainly be
> useful. We've especially been interested in real-time vs. cpu-time, as
> that can often explain strange outliers, expose over provisioning, etc.
>
> cheers,
> Per
>
> >
> > Thanks
> > Sundar
> >
>