Re: [patch 2/2] x86, fpu: lazy allocation of FPU area - v3

Suresh Siddha
2008-03-06T19:27:51Z

On Wed, Mar 05, 2008 at 08:48:01PM +0100, Pavel Machek wrote:
> On Mon 2008-03-03 15:02:46, Suresh Siddha wrote:
> > Only allocate the FPU area when the application actually uses FPU, i.e., in the
> > first lazy FPU trap. This could save memory for non-fpu using apps.
>
> How many such apps are on your system, and how much does this
> 'optimalization' cost?

On a normal kernel boot, where there are 200 or so tasks running, only 20
or so apps seem to be using FPU.

> ISTR glibc always using FPU...?

Apparently not, alteast not on my system. And also going forward, as we extend
this state, thought is nice to have.

thanks,
suresh