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    SubjectHow to stress test? (and 2.0.x SMP yucks)

    I have a spanking new machine destined to be a high-volume production mail
    server. I want to try and stress-test it to see what will break (if
    anything) - I'd like to detect as many problems as possible before we put it
    in the computer room. I'm looking for typical things like
    memory/controller/problems which surface quickly.

    The machine's specs are:

    Dual PII/350
    128MB 100Mhz RAM
    3c590 network adapter
    2x AHA2970
    4x IBM scsi (4GB), destined to be a raid5'ed /var/ partition.
    Small IDE disk for the root (should be 95% read-only).

    I'll be using kernel 2.0.36 to begin with, anxiously anticipating the
    release of 2.2.0. :-)

    My question is, what methods do people use to stress test sw/hw

    I've currently got the machine in lots of tight loops making TCP connections
    to itself constantly, and compiling the kernel willy-nilly, but I was
    wondering if any of you had any better ideas for me.

    Also, are there any obvious problems with this hardware configuration?

    Btw, I think I came up with a pretty clear-cut demonstration of why 2.0.x
    SMP isn't good enough:

    dd if=/dev/urandom bs=1024k count=24 | gzip -c |zcat >/dev/null

    locks the machine up reeeal tight for 1-2 seconds, with incredibly delayed
    (or missing) responses from the console itself (just switching VTs could
    take 2-3 seconds). This is actually bad enough to be a primitive denial of
    service attack..

    This same command didn't have any noticable effect on my trusty old
    single-processor 5x86/160 here at home, so it appears that enabling SMP can
    in some cases cause a performance hit instead of a gain. (I suppose this is
    probably old news, but I thought I'd see if any interesting discussions
    would result from my experience.. ;)

    Thanks in advance, and happy holidays!

    Bjarni R. Einarsson [ PGP: 02764305 / B7A3AB89 ] -=- -=- Juggler@IRCnet

    * *
    Encrypt the covert narcotics, launder nuclear biotechno cash on
    the way to Swiss with your GSM phone - are you paranoid enough?

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