RFR: 8027960: Assertion assert(end >= start) failed during nightly testing on solaris
Stefan Johansson
stefan.johansson at oracle.com
Mon Nov 11 13:23:03 UTC 2013
On 2013-11-11 10:02, Thomas Schatzl wrote:
> Hi Jon,
>
> On Fri, 2013-11-08 at 10:52 -0800, Jon Masamitsu wrote:
>> Stefan,
>>
>> Change looks good.
Thanks for looking at this.
>>
>> There are _gen_alignments and _space_alignments in CollectorPolicy.
>> Where those are initialized there is no calculation of a new_alignment
>> based on page size. For example,
>>
>> void MarkSweepPolicy::initialize_alignments() {
>> _space_alignment = _gen_alignment = (uintx)Generation::GenGrain;
>> _heap_alignment = compute_heap_alignment();
>> }
>>
>> Should those places be calculating and using a new_alignment?
> I am not completely sure what the question is, and whether Jesper's
> reply already replied or not, but as far as I can tell the question
> seems to be why the MarkSweepPolicy (for serial gc) does not take page
> size into account for space and generation alignment.
>
> As far as I know, only Parallel GC ever did that as it is also the only
> collector that is NUMA aware, so I assume this is the reason why that
> collector does. All collectors align the heap alignment to large page
> size though if large pages are used.
>
> Not really an answer, I know - but we can make an rfe/bug from it I
> think.
>
> Thomas
>
Thanks Jesper and Thomas for your input on this. I agree that we might
want to look at having spaces and generations page-aligned for all
collectors.
Jon, if you are satisfied with those answers I'll go ahead and get this
patch pushed.
Cheers,
Stefan
More information about the hotspot-gc-dev
mailing list