lkml.org 
[lkml]   [2000]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: Slow pthread_create() under high load
Alan Cox wrote:
>
> > If you want to see this changes get the kernel changes in place.
> > There are various patches floating around which combined will allow a
> > correct and fast implementation. But they were not added.
>
> The problem he is seeing however appears unrelated to the fact posix
> threads is a braindamaged pile of crap. Its because the scheduler penalises
> across forks as part of its fairness approach. Ingo showed that was in
> fact wrong and posted some algorithm changes for 2.3.9x

So what you are saying is that the scheduler changed after 2.3.9 to make the
forks faster under high load? Will those changes make it to 2.4 ?

Could somebody also elaborate on "the scheduler penalizes across forks" for
those who are not as familiar with the kernel internals/jargon? Does that mean
that a process that has called fork()/clone() automatically gets punished for
this great sin by getting its priority lowered?

If the above is correct, how long does the punishment last?

--
Sasha Pachev

+------------------------------------------------------------------+
| TcX ____ __ _____ _____ ___ == mysql@tcx.se |
| /*/\*\/\*\ /*/ \*\ /*/ \*\ |*| Sasha Pachev |
| /*/ /*/ /*/ \*\_ |*| |*||*| mailto:sasha@mysql.com |
| /*/ /*/ /*/\*\/*/ \*\|*| |*||*| Provo, Utah, USA |
| /*/ /*/ /*/\*\_/*/ \*\_/*/ |*|____ |
| ^^^^^^^^^^^^/*/^^^^^^^^^^^\*\^^^^^^^^^^^ |
| /*/ \*\ Developers Team |
+------------------------------------------------------------------+

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:57    [W:0.171 / U:0.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site