[Pacemaker] DRBD < LVM < EXT4 < NFS performance

[Florian Haas]

On Sun, Jun 10, 2012 at 4:13 PM, Jake Smith <jsmith at argotec.com> wrote:
> I ran into that (scheduler change) also after upgrading. I only accidentally
> stumbled onto that fact. I wish Ubuntu had made it a little clearer that not
> having a separate server kernel had more implications than just kernel!

It's correct that the default I/O scheduler was one of the things
where an Ubuntu "server" kernel would differ from a "desktop" kernel.
However, it's prudent in a system with a reasonably high-performance
I/O subsystem (whether that box is being used for DRBD or not) to
always set the scheduler to deadline either in your /etc/sysfs.conf
(as Ubuntu has been shipping with sysfsutils for a while, albeit in
universe) or in your bootloader configuration.

Cheers,
Florian

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