Re: Scheduling problems

From: Rob Weir (rweir_at_ertius.org)
Date: 05/11/04

  • Next message: Rob Weir: "Re: Problem with newly installed kernel-2.6.3"
    Date: Tue, 11 May 2004 20:11:35 +1000
    To: debian-user@lists.debian.org
    
    
    

    On Fri, May 07, 2004 at 02:22:50PM +0100, Chris Boot said
    > Hi,
    >
    > I'm having several problems concerning scheduling on my linux box. I'm
    > running it as a server and therefore I'd like it to be as reliable as
    > possible, but several niggling factors force me to reboot the box
    > relatively often.
    >
    > The biggest problem I have is if there is no CPU idle time (as reported
    > by top(1)) processes take a very long time to start up, and sometimes
    > even fail to start entirely. I can trigger this very easily and it is
    > very reproducible. I tried to run the Distributed.net client at some
    > point but it ground my system to a halt (even nice'd to 19). This
    > prevents me from logging in using SSH to kill the offending process, or
    > checking my email, or any other task that requires starting processes.

    You say below that you have 1GB of RAM, are you using highmem? This is
    all I can think of, and would be a kernel bug...do you see anything
    related on http://bugzilla.kernel.org/?

    > The next biggest problem is related to the above, I think. When I
    > connect to my box using SSH, and the connection is broken somehow, the
    > SSHd process takes up all the available CPU after just a couple of
    > seconds. All I need to do to trigger this is to connect to the server,
    > then kill the SSH client process. After a few seconds, the server
    > process reaches 99.9% CPU usage:
    >
    > [bootc@arcadia bootc]$ pa | grep notty
    > bootc 24408 99.9 0.4 10688 3928 ? R 14:15 0:38 sshd:
    > bootc@notty
    > bootc 24448 0.0 0.0 1576 496 pts/7 S+ 14:16 0:00 grep
    > notty

    No idea about this, I can't imagine why SSH would suddenly take so much
    CPU time. Is there anything in the ssh Debian bug list about this?

    -- 
    Rob Weir <rweir@ertius.org> | mlspam@ertius.org  |  Do I look like I want a CC?
    Words of the day:  Ron Brown Lon Horiuchi enigma nitrate argus Freeh government
    
    

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  • Next message: Rob Weir: "Re: Problem with newly installed kernel-2.6.3"

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