svn commit: r247319 - in projects/calloutng/sys: kern sys

[Attilio Rao]

On Tue, Feb 26, 2013 at 4:25 PM, Alexander Motin <mav at freebsd.org> wrote:
> Author: mav
> Date: Tue Feb 26 15:25:43 2013
> New Revision: 247319
> URL: http://svnweb.freebsd.org/changeset/base/247319
>
> Log:
>   Optimize callout_process() to use less variables and less conditions to
>   implement the same logic.  Now it fits better into CPU registers, and
>   according to PMC significntly reduces number of resource stalls, reducing
>   consumed by it CPU time during usleep(1) benchmark by 30%.

Is that all improved i-cache capacity and improved dynamic branch
prediction (hwpmc has counters for both FWIW)?

Attilio


-- 
Peace can only be achieved by understanding - A. Einstein