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

[Felix Fietkau]

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.
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> 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.
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