Re: [resent PATCH] Re: very slow parallel read performance

From: Marc (pcg@goof.com)
Date: Sun Aug 26 2001 - 18:24:39 EST


On Sun, Aug 26, 2001 at 11:07:07PM +0200, Daniel Phillips <phillips@bonn-fries.net> wrote:
> To recap, you made these changes:
>
> - Changed to -ac
> - Set max-readahead through proc
>
> Anything else? Did you change MAX_SECTORS?

no, I tinkered a lot with my server (freeing up memory), which obviously
helped somewhat and increased socket buffers to 256k max., makeing i/o
more chunky and thus more efficient. i also use more than one reader
thread: under linus' kernels more than one thread made the situation
worse, on the ac kernels they seem to slightly improve throughout, up to a
point.

> > no longer thrashing. And linux does the job nicely ;)
> Good, but should we rest on our laurels now?

well, linux-2.4 has a lot of dark corners that need improving, but the
machine does no longer totally misbehave (4 or 5 mb/s is debatable, but
2mb/s with more memory and higher load is not ;). it's now acceptable to
me ;)

-- 
      -----==-                                             |
      ----==-- _                                           |
      ---==---(_)__  __ ____  __       Marc Lehmann      +--
      --==---/ / _ \/ // /\ \/ /       pcg@goof.com      |e|
      -=====/_/_//_/\_,_/ /_/\_\       XX11-RIPE         --+
    The choice of a GNU generation                       |
                                                         |
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Fri Aug 31 2001 - 21:00:21 EST