[rhelv6-beta-list] Apache benchmark RHEL 5 vs. RHEL 6

[Simon Matter]

> On Mon, Nov 08, 2010 at 09:58:12PM -0500, Ashley Penney wrote:
>> One thing to consider is the 'nobarrier' option for ext4 - apparently
>> makes
>> a big performance difference.
>
> This is probably it. This was discussed ad infinitum when it was
> changed upstream, and caused a huge performance regression across
> pretty much every workload.

But don't barriers affect mostly writes? If yes, is it because of the logs
and atime? 80% still looks like too much, maybe it's so bad because of the
virtualized environment?

Simon