Hi,

find hereunder the measurements I sent to Jeff.

If someone think this patch is really useful for 2.6 I can make the
port.

Regards,
Laurent
Please CC: me, as I'm not in the mailing list.

Le lun 17/05/2004 à 22:08, roland a écrit :
> hi !
> has this / will this be ported to 2.6 ?
> have there been made further performance comparisons ?
> regards
> roland
> 
> 
> >Well, we just looked at the context switches. We started 3 UMLs which
> >were doing a make world for xfree. Without patches the number of
> >context switches per second was around 60k, with the patch it was around
> >40k - so it's noticeable, at least from the cs.
> >Sven
> 
> ----- Original Message ----- 
> From: "Jeff Dike" <jdike@addtoit.com>
> To: <user-mode-linux-devel@lists.sourceforge.net>
> Sent: Sunday, February 29, 2004 6:35 AM
> Subject: [uml-devel] [PATCH] host context switch reduction
> 
> 
> > The patches below are from Laurent Vivier who didn't make them public.  They
> > add a new feature to ptrace on the host which cuts down on the number of
> > context switches needed for a UML system call, plus makes UML use it.
> > 
> > There's some interest in this, so I'm putting it out as-is.  I haven't played
> > with it.
> > 
> > Laurent did some performance testing and found ~40% speedup on a getpid
> > loop, and a 3.5% speedup on a kernel build.
> > 
> > Jeff
> > 
> >