RFR (S): JEP-142: Reduce Cache Contention on Specified Fields

Aleksey Shipilev aleksey.shipilev at oracle.com
Mon Nov 26 02:09:50 PST 2012

Well, yeah. Hardware specifics leaking into high-level application code,
that's a fact of life for high-performance code, whatever language is


On 11/26/2012 02:01 PM, Kirk Pepperdine wrote:
> I'm not arguing against the optimization, I clearly see the value. I'm just suggesting this is not a "Thinking in Java" solution, it's a "Thinking in C++" solution. Don't misunderstand, both are valid ways of thinking when done in the right context.  ;-)
> -- Kirk
> On 2012-11-26, at 9:55 AM, Aleksey Shipilev <aleksey.shipilev at oracle.com> wrote:
>> On 11/26/2012 01:22 AM, Kirk Pepperdine wrote:
>>> My mantra has always been, measure, don't guess.
>> ...said the guy before start guessing about the impact for this
>> annotation :D
>> We know exactly where this helps, and where library developers sorely
>> need this functionality, so here we are. In a few years, having this
>> annotation around would help us to understand if that is applicable on
>> broader scope, and what are the preconditions to be granted while
>> applying this optimization. Having all that on the table, we could
>> finally rationalize the budget needed to research and bringing on the
>> automatic field layout. Before that, it's preposterous to invest several
>> man-years into developing the optimization now known to be needed in a
>> handful of cases.
>> -Aleksey.

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