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 

Jon, if you are satisfied with those answers I'll go ahead and get this 
patch pushed.


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