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Subject: Re: kern.sched.quantum: Creepy, sadistic scheduler
To: George Mitchell <george+freebsd@m5p.com>, freebsd-stable@freebsd.org
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From: Julian Elischer <julian@freebsd.org>
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On 4/4/18 9:32 pm, George Mitchell wrote:
> On 04/04/18 06:39, Alban Hertroys wrote:
>> [...]
>> That said, SCHED_ULE (the default scheduler for quite a while now) was designed with multi-CPU configurations in mind and there are claims that SCHED_4BSD works better for single-CPU configurations. You may give that a try, if you're not already on SCHED_4BSD.
>> [...]
> A small, disgruntled community of FreeBSD users who have never seen
> proof that SCHED_ULE is better than SCHED_4BSD in any environment
> continue to regularly recompile with SCHED_4BSD.  I dread the day when
> that becomes impossible, but at least it isn't here yet.      -- George
>
for a single CPU you really should compile a kernel with SMP turned 
off and 4BSD scheduler.

ULE is just trying too hard to do stuff you don't need.