Re: interactive task starvation

Willy Tarreau
2006-03-21T06:47:40Z

Hi Mike,

On Mon, Mar 20, 2006 at 08:09:13AM +0100, Mike Galbraith wrote:
(...)
> For those interested in these kind of things, here are the numbers for
> 2.6.16-rc6-mm2 with my [tarball] throttle patches applied...
>
> [root]:# time netstat|grep :81|wc -l
> 1681
>
> real 0m1.525s
> user 0m0.141s
> sys 0m0.136s
> [root]:# time netstat|grep :81|wc -l
> 1491
>
> real 0m0.356s
> user 0m0.130s
> sys 0m0.114s
> [root]:# time netstat|grep :81|wc -l
> 1527
>
> real 0m0.343s
> user 0m0.129s
> sys 0m0.114s
> [root]:# time netstat|grep :81|wc -l
> 1568
>
> real 0m0.512s
> user 0m0.112s
> sys 0m0.138s
>
> ...while running with the same apache loadavg of over 10, and tunables
> set to server mode (0,0).
>
> <plug>
> Even a desktop running with these settings is so interactive that I
> could play a game of Maelstrom (asteroids like thing) while doing a make
> -j30 in slow nfs mount and barely feel it. In a local filesystem, I
> could't feel it at all, so I added a thud 3, irman2 and a bonnie -s 2047
> for good measure. Try that with stock :)
> </plug>

Very good job !
I told Grant in a private email that I felt confident the problem would
quickly be solved now that someone familiar with the scheduler could
reliably reproduce it. Your numbers look excellent, I'm willing to test.
Could you remind us what kernel and what patches we need to apply to
try the same, please ?

Cheers,
Willy