On 2014-10-08 09:36:03 Steve Langasek <[email protected]> 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? > I also think it's categorically wrong to say that there's minimal chance of > regression. These schedulers have pretty fundamentally different > characteristics, and where CFQ behaves pathologically for one process (the > indexer), deadline will behave pathologically for others. How much testing did Ubuntu do before changing away from upstream's default? Which aspects of Ubuntu performed "pathologically" that necessitated the change? > I don't think it's at all acceptable to work around a kernel bug in a > kubuntu-settings SRU. The right fix is to resolve this in the kernel > package instead. (Bug #1310402) Cc:ing the kernel team. > > Also, what exactly do you mean when you say baloo doesn't "implement ionice > support"? The 'ionice' tool is part of the base system (util-linux). It > would be a simple matter of packaging to always run baloo under ionice. To clarify: Baloo _does_ use ionice. It's the lack of support for ionice in the deadline scheduler that's the root of the problem here. ...Steve Riley -- kubuntu-devel mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-devel
