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SubjectRe: Interesting pentium-memcpy results
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Chris Evans <mailto:chris@ferret.lmh.ox.ac.uk> writes:
>I just compared 2.1.46 vs. 2.1.46+pentium memcpy patch, and interestingly
>enough found that the UNIX byte benchmarks tended to _drop_ a fair bit,
>with the exception of process creation and execl throughput. (Note that I
>only ran the basic 'system' tests - TCP bandwidth etc. to be determined
>when I find the newer benchmarks)
>

>It does however show us that there still is performance to be gained. I
>presume the process creation test will be using fork() which does a lot of
>memcpy'ing of various process credentials in kernel space.
>
I haven't done the research to verify how well this will work under
Linux, but for large a memcpy on the P5 we may wanna consider using the FP
unit using double precision read and writes. I have sample code if anyone is
interested.
--
Benjamin Saller Bender <case@AppliedTheory.com>
AppliedTheory Communications Software Engineering Group
http://AppliedTheory.com/ Sentio aliquos togatos contra me conspirare.



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