Re: LMbench results for 2.5.40

From: Bill Davidsen (
Date: Tue Oct 08 2002 - 13:55:01 EST

On Tue, 1 Oct 2002, Larry McVoy wrote:

> By the way, the place you will probably see variance in LMbench is in the
> context switch benchmarks, it's almost certainly due to randomness in
> cache layout and there isn't a thing we can do about it. You can run a
> zillion runs to get an average but please realize that is an *average*.
> The context switch number are accurate, the low ones represent no cache
> collisions and the high ones represent lots of cache collisions.
> FYI. I don't like it either.

Thank you, that explains some things I've seen in my context switching
benchmark as well, which uses a bunch of different services to transfer
tiny data from on process to another.

Time for some statistical jiggery-pokery, dust off deviant mean or some

bill davidsen <>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.

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