[SRU] Set the default IO scheduler to CFQ in Kubuntu Trusty
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
kubuntu-settings (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned | ||
Trusty |
Fix Released
|
Undecided
|
Unassigned | ||
Utopic |
Fix Released
|
Undecided
|
Unassigned |
Bug Description
[Impact]
Using deadline causes performance regressions in Baloo. See bug 1310402 for an example.
[Test Case]
* Use Kubuntu trusty until it slows to a crawl
* Upgrade kubuntu-settings
* Reboot
* Make sure boot completes successfully
* Make sure IO scheduler is set to CFQ on boot in case you have a HDD : cat /sys/block/
* use it and verify it no longer slow to a crawl
[Test Case for Unity]
- installing an Ubuntu precise desktop with unity7 (which I believe was the
last release using cfq by default) and the .0 kernel (3.2.0)
- using the system for a bit to try to reproduce the original problem -
application windows becoming grayed out by the WM under normal usage,
indicating that the app is not responding
- changing the scheduler to deadline and testing to see if the problem
persists or resolves itself
- upgrading to the trusty backport kernel (linux-
- verifying that the desktop behaves correctly with the default deadline
scheduler
- changing the scheduler to cfq and testing whether the original problem
recurs
[Regression Potential]
None that I can think of, deployment has been successful on Utopic
Changed in kubuntu-settings (Ubuntu Utopic): | |
status: | New → Fix Released |
description: | updated |
tags: | added: kubuntu |
(wearing both my kubuntu and kde dev hat)
Super important bug. It can make IO come to a crawl making desktop systems unusable on rationale media, which in turn makes users unhappy, users complain to upstream, user complain to us, users complain to users. This is not good. It makes people waste time on a perfectly solvable issue, it annoys both upstream and kubuntu developers.
All in all this gives a bad impression and must absolutely be resolved, in particular since 14.04 is a LTS release. Having people's systems come to a crawl every once in a while until the next LTS comes out is absolutely not acceptable.