Vladimir.Kozlov at Sun.COM
Mon Feb 23 05:47:00 PST 2009
Use _LP64 define
Vladimir Kozlov wrote:
> Christian Thalinger wrote:
>> On Mon, 2009-02-23 at 07:29 -0500, Paul Hohensee wrote:
>>> Imo, the #ifdef's are ok in this case because they're quite limited.
>>> Vladimir set prefetch distances based on experiment. The difference
>>> between 320 and 384 is a single cache line. It seems to me that 32
>>> and 64-bit would be the same because it's the same hardware, except
>>> that it may be that 64-bit code is faster than 32-bit code, thus would
>>> require a slightly greater prefetch distance.
> No, it is because different average allocation object's size (different
> oop size).
>>> 32-bit doesn't use the Prefetchxxx switches because there's no common
>>> prefetch instruction for 32-bit that can be used in C++ code. #ifdef is
>>> ok here.
> That is correct.
>> Paul, thank you for the explanation. Last question: should I use the
>> _LP64 or AMD64 define?
>> -- Christian
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