[SRU] Set the default IO scheduler to CFQ in Kubuntu Trusty

[Marc Deslauriers]

On 14-10-08 01:25 PM, Steve Riley wrote:
> On 2014-10-08 09:36:03 Steve Langasek <steve.langasek at ubuntu.com> wrote:
>>
>> I don't think it's at all appropriate for a desktop environment to install a
>> udev rule which changes the kernel scheduler.  That's a severe layering
>> violation, and it means that anyone who installs kubuntu-desktop on an
>> existing system will significantly change the performance characteristics of
>> that system.
> 
> To my knowledge, Ubuntu is the only distribution that changes upstream's default from CFQ to deadline. I read the Launchpad bugs and the linked IRC logs; it seems that the reasons for making the change (around the time of Precise) have been largely forgotten. Perhaps it's worth revisiting the decision?
> 

Actually, I believe RHEL 7 uses deadline by default on all devices except SATA
disks.

Marc.