Interesting pentium-memcpy results

Chris Evans (chris@ferret.lmh.ox.ac.uk)
Mon, 28 Jul 1997 16:55:45 +0100 (BST)


Hi,

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)

This is most interesting since I used to swear by the patch.

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.

Chris