Re: decreasing interrupt CPU load

From: Steven Hartland (killing_at_multiplay.co.uk)
Date: 10/20/04

  • Next message: Uwe Doering: "Re: decreasing interrupt CPU load" 
    To: "Uwe Doering" <gemini@geminix.org>, <freebsd-performance@freebsd.org>
Date: Wed, 20 Oct 2004 21:37:47 +0100

    Actually it does work quite well on an SMP machine if you comment
    said lines out :)

        Steve
    ----- Original Message -----
    From: "Uwe Doering" <gemini@geminix.org>
    To: <freebsd-performance@freebsd.org>
    Sent: Wednesday, October 20, 2004 9:16 PM
    Subject: Re: decreasing interrupt CPU load

    > Since you mentioned earlier that you run this on an SMP system, are you
    > aware that device polling is available only for single CPU kernels, that
    > is, not in SMP mode? This is poorly documented, unfortunately. You can
    > find out about it by looking at the first couple of lines of
    > 'sys/kern/kern_poll.c'.
    >
    > Depending on what else you do on this server you might be better off
    > with running it in single CPU mode, with device polling enabled (kernel
    > compiled with DEVICE_POLLING and HZ=1000). This could make a
    > considerable difference with the fxp driver already. I suggest to try
    > it out before you start making changes to the hardware.

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  • Next message: Uwe Doering: "Re: decreasing interrupt CPU load"

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