Re: Current ULE state and plans (was Re: HMP scheduling on FreeBSD)

On 1/19/26 15:51, Olivier Certner wrote:
>> Why remove functioning code that people actually use?
> 
> How can you be sure it is functioning correctly?  Have you reviewed it?  Has it been tested on a variety of workloads?  What does guarantee it will not break, more or less badly, when some code surrounding it is changed, even when these changes are done carefully?
> 
> And who is using it, exactly? You count for 1. Given the past threads on the topic, I expect a few more, but can we even reach 10 or 20, I wouldn't bet on it.
> [...]

Speaking as the guy who periodically bitched about what ULE was doing
to misc/dnetc until someone pointed out idprio to me (a setting that
4BSD couldn't care less about but that ULE goes nuts over if you set it
wrong), count me as a continuing user of 4BSD.  Because it just works.

Anecdotally, I don't personally observe the purported interactivity
improvement ascribed to ULE, either, but I can't give you numbers on it.

And why shouldn't people try to create other new schedulers?  And should
we not at least keep testing that the scheduler interface is simple and
promotes scheduler modularity?                               -- George