Date: Sat, 24 Dec 2011 01:02:40 +0200 From: Andriy Gapon <avg@FreeBSD.org> To: Adrian Chadd <adrian@FreeBSD.org> Cc: freebsd-stable@FreeBSD.org, Steve Kargl <sgk@troutmask.apl.washington.edu> Subject: Re: SCHED_ULE should not be the default Message-ID: <4EF50890.8030509@FreeBSD.org> In-Reply-To: <CAJ-Vmon69r-341aMutBAHT_VCMkM9afzu=4sBd7s7zqFiK%2BEVA@mail.gmail.com> References: <4EE1EAFE.3070408@m5p.com> <CAJ-FndBSOS3hKYqmPnVkoMhPmowBBqy9-%2BeJJEMTdoVjdMTEdw@mail.gmail.com> <20111215215554.GA87606@troutmask.apl.washington.edu> <CAJ-FndD0vFWUnRPxz6CTR5JBaEaY3gh9y7-Dy6Gds69_aRgfpg@mail.gmail.com> <20111222005250.GA23115@troutmask.apl.washington.edu> <20111222103145.GA42457@onelab2.iet.unipi.it> <20111222184531.GA36084@troutmask.apl.washington.edu> <4EF37E7B.4020505@FreeBSD.org> <20111222194740.GA36796@troutmask.apl.washington.edu> <CAJ-VmokeyDrKb-yQkzTm8tnOYcRm603hz%2B6nen10F3zFQVmCEQ@mail.gmail.com> <20111223191146.GA56232@troutmask.apl.washington.edu> <CAJ-Vmon69r-341aMutBAHT_VCMkM9afzu=4sBd7s7zqFiK%2BEVA@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
on 24/12/2011 00:49 Adrian Chadd said the following: > Does ULE care (much) if the nodes are hyperthreading or real cores? > Would that play a part in what it tries to schedule/spread? An answer to this part from the theory. ULE does care about physical topology of the (logical) CPUs. So, for example, four cores are not the same as two core with two hw threads from ULE's perspective. Still, ULE tries to eliminate any imbalances between the CPU groups starting from the top level (e.g. CPU packages in a multi-socket system) and all the way down to the individual (logical) CPUs. Thus, given enough load (L >= N) there should not be an idle CPU in the system whatever the topology. Modulo bugs, of course, as always. -- Andriy Gapon
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4EF50890.8030509>