FreeBSD 5.2.1: Mutex/Spinlock starvation?

[John Baldwin]

On Monday 07 June 2004 01:35 pm, Ali Niknam wrote:
> > There isn't a timeout.  Rather, the lock spins so long as the current
> > owning thread is executing on another CPU.
>
> Interesting. Is there a way to 'lock' CPU's so that they always run on
> 'another' CPU ?

Not in userland, no.

> Unfortunately as we speak the server is down again :( This all makes me
> wonder wether I should simply go back to 4.10.
> I decreased the maximum number of apache children to 1400 and the server
> seems to be barely holding on:
> last pid:  2483;  load averages: 75.77, 28.63, 11.40    up 0+00:04:32
> 19:35:07
> 1438 processes:2 running, 294 sleeping, 1142 lock
> CPU states:  6.2% user,  0.0% nice, 62.6% system,  7.5% interrupt, 23.8%
> idle
> Mem: 698M Active, 27M Inact, 209M Wired, 440K Cache, 96M Buf, 1068M Free
> Swap: 512M Total, 512M Free
>
>
> Are there anymore quite stable things to do ? That is except for upping to
> current, which I frankly feel is too dangerous...

Nothing that I can think of off the top of my head.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org