Date: Wed, 10 Dec 2003 23:03:17 -0500 (EST) From: Jeff Roberson <jroberson@chesapeake.net> To: Andy Farkas <andyf@speednet.com.au> Cc: current@freebsd.org Subject: Re: ULE and current. Message-ID: <20031210230206.R4201-100000@mail.chesapeake.net> In-Reply-To: <20031211085336.O13173@hewey.af.speednet.com.au>
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On Thu, 11 Dec 2003, Andy Farkas wrote:
>
> The scheduling of nice processes seems to be broken:
This is actually a problem in the load balancer. It's not taking nice
into consideration when attempting to balance the load.
>
> team2# nice -7 sh -c "while :; do echo -n;done" &
> team2# nice -7 sh -c "while :; do echo -n;done" &
> team2# sleep 120; top -S
>
> PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND
> 675 root 133 -7 1576K 952K CPU1 1 1:52 75.78% 75.78% sh
> 676 root 133 -7 1576K 952K RUN 1 1:39 73.44% 73.44% sh
> 12 root -16 0 0K 12K RUN 0 18:46 55.47% 55.47% idle: cpu0
> 11 root -16 0 0K 12K RUN 1 7:00 0.00% 0.00% idle: cpu1
>
>
> Adding a third nice process eliminates the idle time, but cpu% is still bad:
>
> team2# nice -7 sh -c "while :; do echo -n;done" &
> team2# sleep 120; top -S
>
> PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND
> 705 root 133 -7 1576K 952K CPU0 0 1:53 100.78% 100.78% sh
> 675 root 133 -7 1576K 952K RUN 1 12:12 51.56% 51.56% sh
> 676 root 133 -7 1576K 952K RUN 1 11:30 49.22% 49.22% sh
> 729 root 76 0 2148K 1184K CPU1 1 0:00 0.78% 0.78% top
> 12 root -16 0 0K 12K RUN 0 24:00 0.00% 0.00% idle: cpu0
> 11 root -16 0 0K 12K RUN 1 7:00 0.00% 0.00% idle: cpu1
I agree that 100.78% is wrong. Also, the long term balancer should be
kicking one sh process off of the doubly loaded cpu every so often. I'll
look into this, thanks.
Cheers,
Jeff
>
>
> The box is a dual P133 running -current from 8th Dec.
>
> --
>
> :{ andyf@speednet.com.au
>
> Andy Farkas
> System Administrator
> Speednet Communications
> http://www.speednet.com.au/
>
>
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