harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Rana Dasgupta" <rdasg...@gmail.com>
Subject Re: [drlvm]Leave classunloading on by default?
Date Tue, 20 Nov 2007 17:38:27 GMT
Sorry, that's a typo "Unloading happens when major collections happen
naturally due to heap conditions. So there should be no difference...etc."

On 11/20/07, Rana Dasgupta <rdasgupt@gmail.com> wrote:
>
> Hi Aleksey,
>    No we cannot turn on force_major_collect=true, you are right. Only turn
> on ignore_vtable_tracing to be true by default. The force_major_collect=true
> is not needed for CU, only for testing. Unloading happens when major
> collections happen naturally due to heap conditions and is not caused by
> class unloading. So there should be no difference. The overhead of vtable
> tracing is small.
>
> Thanks,
> Rana
>
> On 11/20/07, Aleksey Shipilev <aleksey.shipilev@gmail.com> wrote:
>
> > Hi, Rana!
> >
> > On Sep 24, 2007 12:11 AM, Rana Dasgupta <rdasgupt@gmail.com > wrote:
> > > Harmony DRLVM has recently added a class unloading feature. It's now
> > > ready for trial and regular use. It's not on by default, and to turn
> > > on the feature, a couple of options are needed:
> > >  -XX:gc.ignore_vtable_tracing=false  -XX:gc.force_major_collect=true
> > AFAIU, forcing major collect will disable minor collection entirely,
> > so we will have the major collection every time the heap is full. If
> > my understanding is correct, then GC pauses will be significantly
> > larger thus degrading workload performance. Have you counted
> > minor/major collection ratios for CU on/off?
> >
> > Thanks,
> > Aleksey.
> >
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message