Journaling is killing response time

[Nils Kassube]

Bruce Marshall wrote:
> Lately I've been having really bad response intermittently, but often
> enough it is really irritating.  For example, I will try to kill a
> program like T-bird, and it will take so long that I get the "not
> responding" message. But the problem is that it CAN'T respond due to
> being blocked by the journaling I/O.  If I tell it to wait, it will
> finally close.
> 
> I've been googling the problem and have changed a lot of mount parms
> but nothing seems to help.  Running  14.10 on an AMD64 machine and
> this problem seems to have cropped up from the latest batch of
> updates, within the last one or two weeks.

Maybe the mount parms don't matter but the I/O scheduler for the disk?
After sending my previous mail I did some digging and found the thread
starting with the mail [1] and the bug report [2] mentioned in that
mail. Maybe your problems (and mine) are related to the scheduler switch
from deadline to cfq. OTOH, then you should have seen the problems as
long as you are using 14.10. At least I'll try if it gets better if I
change the scheduler to deadline.


Nils

[1] <https://lists.ubuntu.com/archives/kubuntu-devel/2014-October/008808.html>
[2] <https://launchpad.net/bugs/1378789>