Re: Dual XEON - >>SLOW<< on SMP

From: Jeff V. Merkey (jmerkey@vger.timpanogas.org)
Date: Wed Nov 08 2000 - 14:17:32 EST


On Wed, Nov 08, 2000 at 09:28:54AM -0500, Richard B. Johnson wrote:
> On Tue, 7 Nov 2000, Jeff V. Merkey wrote:
>
> >
> > Marc Lehman verified that PII systems will generate tons of AGIs with
> > gcc. Perhaps this is the cause of this problem. You could run EMON and
> > see if there is something obvious in the numbers ...
> >
> > Jeff
> >
>
> Here are some tests:
>
> Before the tests, I do:
> `ifconfig eth0 down`
> `kill -TERM -1`
>
> Then I disconnect my ethernet cable to get rid of those interrupts.
>
>
> This is the test-script:
> make clean
> time make -j 10 bzImage
>
> It is executed as `sh test.sh &>World.Log &` .
>
>
> This is Linux 2.4.0-test9
>
> This is a kernel build with NMI watchdog turned OFF:
> 349.04user 19.83system 3:21.96elapsed 182%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+0minor)pagefaults 0swaps
>
>
> This is a kernel build with NMI watchdog turned ON:
> 348.23user 18.84system 3:57.14elapsed 154%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+0minor)pagefaults 0swaps
>
> The elapsed time went from 3:21 to 3:57.
>
>
> This is Linux 2.2.17
>
> This is the kernel build (the exact same build as above).
> 214.91user 12.93system 2:37.00elapsed 145%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+0minor)pagefaults 0swaps
>
> The original elapsed time when booting 2.2.17 was 2:37. It is now 3:57.
>
> This is, in every case, rebuilding the exact same kernel.
>
> It doth appearith asthough ithsucks.
>

I'll attempt to reproduce. I've got live internet servers running on 2.2.18-19
and am not seeing this.

Jeff

>
> Cheers,
> Dick Johnson
>
> Penguin : Linux version 2.4.0 on an i686 machine (799.54 BogoMips).
>
> "Memory is like gasoline. You use it up when you are running. Of
> course you get it all back when you reboot..."; Actual explanation
> obtained from the Micro$oft help desk.
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Wed Nov 15 2000 - 21:00:12 EST