Re: linux scheduler limitations?

J . A . Magallon
2001-03-29T22:35:06Z

On 03.30 Fabio Riccardi wrote:
>
> Despite of all apparences this method performs beautifully on Linux, pthreads
> are
> actually slower in many cases, since you will incur some additional overhead
> due
> to thread synchronization and scheduling.
>

It all depends on your app, as every parallel algorithm. In a web-ftp-whatever
server, you do not need any synchro. You can start threads in free run and
let them die alone.

> The problem is that beyond a certain number of processes the scheduler just
> goes
> bananas, or so it seems to me.
>
> Since Linux threads are mapped on processes, I don't think that (p)threads
> woud
> help in any way, unless it is the VM context switch overhead that is playing a
> role here, which I wouldn't think is the case.
>

You said, 'mapped'.
AFAIK, that is the advantage, you can avoid the VM switch by sharing memory.

--
J.A. Magallon # Let the source
mailto:jamagallon@able.es # be with you, Luke...

Linux werewolf 2.4.2-ac28 #1 SMP Thu Mar 29 16:41:17 CEST 2001 i686