Optimized kernel builds: the straight dope

[Matt Zimmerman]

On Sun, Aug 20, 2006 at 03:24:12PM -0400, John Richard Moser wrote:
> Matt Zimmerman wrote:
> > Unlike with the kernel, it should be straightforward to benchmark real
> > workloads as well as artificial benchmarks.  For example, a web server
> > benchmark, system boot process, graphics benchmarks...this would require
> > rebuilding many system components in order to construct a compelling test,
> > but that's mostly a matter of CPU cycles.
> > 
> 
> Are you volunteering an i[56]86 build of all world?

I am not.  Let me know if you require further clarification.

> With something like Firefox, you are watching wall-clock time for short
> operations and don't have the resolution to say there's any increase
> unless you DO get something over 20% ("wow this HUGE page rendered in 24
> seconds instead of 30").  Other things never really hit 100% CPU usage,
> and it's hard to measure the minor fluctuations in CPU usage the
> optimizations cause.
> 
> If you have any ideas, I'm open to hearing them.

Set up gdm to do automatic login and stop bootchart only when the login is
complete.  Measure time using bootchart.  That should pull in enough of the
desktop stack to get a meaningful measurement.

This is a multi-minute process on many machines, and a gain of, say, 10%
could be significant.  I highly doubt that compiler optimizations would
approach this, however.

-- 
 - mdz