[clue-tech] 2.6 kernel compile options make Intel CPU slow

[Maxwell Spangler]

On Mon, 2010-07-19 at 15:32 -0600, Jim Ockers wrote:
> Hi CLUEbies,
> 
> I have a curious problem.  We compiled a custom 2.6 Linux kernel for
> an embedded platform.  The target hardware is Intel P4 or AMD.  The
> hardware used to run a 2.4 Linux kernel.  Here is the fast/slowness
> matrix:
> 
>        Intel      AMD
> 2.4    fast       fast
> 2.6    slow       fast

This small bit of data suggests that the 2.6 kernel can run as fast as
the 2.4 but that something about the 2.6 + Intel P4 hardware combination
is slow.

Can you run the same test on a variety of Intel and AMD chips to see if
a pattern develops?  There might be other AMD chips that suffer as well
as other Intel chips that are successful.  Comparing the differences in
chip features might point to why your results here are problematic.

Also, were there any clues in the results of the time command's output?
Any big differences on the level of what time was being used: user vs
sys?

-- 
Maxwell Spangler
========================================================================
        Linux, Unix and Database Administration
        Currently: Boulder, Colorado
        LinkedIn: http://www.linkedin.com/in/maxwellspangler