RFR(14u): 8237375: SimpleThresholdPolicy misses CounterDecay timestamp initialization

[Volker Simonis]

On Fri, Feb 7, 2020 at 1:46 PM Langer, Christoph
<christoph.langer at sap.com> wrote:
>
> Hi Volker,
>
> thanks for having a look here.
>
> > Looks good except that I'd rather use:
> >
> > +    return ((os::javaTimeNanos() - _last_timestamp) /
> > NANOUNITS_PER_MILLIUNIT) > CounterDecayMinIntervalLength;
> >
> > instead of:
> >
> > +    return ((os::javaTimeNanos() - _last_timestamp) / NANOUNITS *
> > MILLIUNITS) > CounterDecayMinIntervalLength;
> >
> > because it looks clearer (and is exactly what nanos_to_millis() also does).
>
> You're right and I would have done that - but unfortunately NANOUNITS_PER_MILLIUNIT was only introduced with 8235741 and I don't want to pull this into my backport here.
>
> So, is the change for 11u also ok?
>

I see. Then it's OK for me. You could use one more pair of parenthesis
(i.e.  (((os::javaTimeNanos() - _last_timestamp) / NANOUNITS) *
MILLIUNITS) to make the expression more clear, but I leave that up to
you. No new review required from my side.

> Thanks
> Christoph
>