Re: SCHED_ULE should not be the default

В Tue, 13 Dec 2011 23:02:15 +0000
Marcus Reid <marcus_at_blazingdot.com> пишет:

> On Mon, Dec 12, 2011 at 04:29:14PM -0800, Doug Barton wrote:
> > On 12/12/2011 05:47, O. Hartmann wrote:
> > > Do we have any proof at hand for such cases where SCHED_ULE
> > > performs much better than SCHED_4BSD?
> > 
> > I complained about poor interactive performance of ULE in a desktop
> > environment for years. I had numerous people try to help, including
> > Jeff, with various tunables, dtrace'ing, etc. The cause of the
> > problem was never found.
> 
> The issues that I've seen with ULE on the desktop seem to be caused
> by X taking up a steady amount of CPU, and being demoted from being an
> "interactive" process.  X then becomes the bottleneck for other
> processes that would otherwise be "interactive".  Try 'renice -20
> <pid_of_X>' and see if that makes your problems go away.

Why, then X is not a bottleneck when using 4BSD?

> Marcus