[LEDE-DEV] [PATCH] kernel: Switch to No-op for the default scheduler.

[rosenp at gmail.com]

On Wed, 2017-11-08 at 10:27 +0100, Felix Fietkau wrote:
> On 2017-11-08 07:18, John Crispin wrote:
> > j
> > 
> > 
> > On 07/11/17 19:41, Rosen Penev wrote:
> > > most users don't have multithreaded workloads though.
> > > 
> > > On Mon, Nov 6, 2017 at 4:43 PM, Dave Taht <dave at taht.net> wrote:
> > > > I happen to like deadline schedulers, and at least from a
> > > > kernel
> > > > perspective, we have a very large set of multithreaded
> > > > workloads.
> > > > 
> > > > So I would not make this change without a very serious set of
> > > > benchmarks
> > > > under load showing it makes a difference.
> > > 
> > > _______________________________________________
> > > Lede-dev mailing list
> > > Lede-dev at lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/lede-dev
> > 
> > I fully agree with dave on this one. changing the default scheduler
> > is 
> > not a small change. please provide benchmarks done on typical
> > router HW 
> > if you would like to see this getting merged.
As Felix said, it's just the I/O scheduler. I'm a bit busy for
benchmarks at this time but I have been using noop for a while now and
have noticed no noticeable regressions.
> 
> It's just the I/O scheduler, not the CPU one. It will have zero
> impact
> on typical router workloads. The only thing that might get slower is
> heavy multi-threaded disk I/O, which is probably an extremely rare
> occurence on LEDE. Also, at least according to that linked phoronix
> benchmark, even on some of these workloads, no-op can be competitive
> ;)
> 
> - Felix