Re: SCHED_4BSD in RELENG_7 disturbs workflow

Jeff Roberson wrote:
> On Tue, 16 Oct 2007, Kris Kennaway wrote:
> 
>> [LoN]Kamikaze wrote:
>>> I know that RELENG_7 is not considered very near-release, but I 
>>> thought I'd
>>> give my 2¢ in the hope that I might have a little influence on the 
>>> scheduler
>>> development to my benefit.
>>>
>>> The switch from RELENG_6 to RELENG_7 went relatively smooth and apart 
>>> from ipw
>>> causing panics. However there is one thing that's disturbing and this 
>>> is the
>>> scheduler. I only have single core machines, so whatever I say only 
>>> applies to
>>> those. If you think single-core machines are no longer important, 
>>> feel free to
>>> ignore this. In deed, just ignore me however much you like.
>>>
>>>> From my perspective scheduling on RELENG_6 was way better. Even on a 
>>>> full
>>> workload like a portupgrade the focused application (both in X and on 
>>> the
>>> console) always received enough cycles to run smoothly and 
>>> applications that
>>> ran in background like audio players also kept on running fine.
>>>
>>> Quite the contrary on RELENG_7. During a portupgrade or even worse 
>>> 'pkgdb -L'
>>> (recovering lost dependencies) audio players (both graphical and 
>>> mplayer)
>>> scatter, either because they don't get the hard-disk or CPU-cycles 
>>> (which one,
>>> I don't know) and the focused application also often hangs. It just 
>>> looks like
>>> occasionally (under load) everything freezes for a second and then 
>>> goes on
>>> relatively normal.
>>>
>>> I've got the impression that things compile a little faster (that 
>>> might be my
>>> imagination, though), but I'd rather have a smooth working experience.
>>>
>>> This is just my view of the situation and I suppose it is only one of 
>>> many. I
>>> bid you be merciful with us single-core people, who cannot afford a 
>>> slick
>>> multi-core machine, because we worry how to pay for our food at the 
>>> end of the
>>> month.
>>
>> Not to say that any problems that might have developed with SCHED_4BSD 
>> should not be fixed, but you should give SCHED_ULE a try since it 
>> brings benefits even for single CPU systems (e.g. better interactive 
>> response).
> 
> It would indeed be good to know if ULE improves things for you.  
> However, there have been a number of other reports about non-scheduler 
> related regressions with x windows on 7.0.  I run 7.0 on a UP laptop 
> without difficulty.  I wonder if it has something to do with a 
> particular device or driver.

Or xorg 7.3 vs 7.2, if this was an older 6.x install.

Kris