Date: Wed, 22 Mar 2023 11:17:51 +0100 From: Matthias Andree <mandree@FreeBSD.org> To: freebsd-hackers@freebsd.org Subject: Re: Periodic rant about SCHED_ULE Message-ID: <8173cc7e-e934-dd5c-312a-1dfa886941aa@FreeBSD.org> In-Reply-To: <a401e51a-250a-64a0-15cb-ff79bcefbf94@m5p.com> References: <a401e51a-250a-64a0-15cb-ff79bcefbf94@m5p.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Am 21.03.23 um 23:52 schrieb George Mitchell: > Yes, you've all heard it before, but I've just reverified on FreeBSD > 13.1-RELEASE-p7 that SCHED_ULE gives terrible performance for "make > buildworld" in the presence of a totally compute-bound job (misc/dnetc > from ports) running at nice 20. World builds in: > 15597 seconds with SCHED_4BSD without dnetc > 20477 seconds with SCHED_4BSD with dnetc > 16006 seconds with SCHED_ULE without dnetc > 50290 seconds with SCHED_ULE with dnetc. > When I ask why SCHED_ULE is the default scheduler, I have been told more > than once that there is some circumstance in which it gives superior > performance. But no one seems to know what circumstance that is. Guess > what! I propose that SCHED_4BSD be the default scheduler. -- George > Can you please also give figures how much CPU time has been allotted to dnetc in that respective situations? -- Matthias Andree
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?8173cc7e-e934-dd5c-312a-1dfa886941aa>