Date: Mon, 25 Feb 2008 19:55:04 -1000 (HST) From: Jeff Roberson <jroberson@chesapeake.net> To: David Xu <davidxu@freebsd.org> Cc: current@freebsd.org Subject: Re: Topology aware scheduling algorithm. Message-ID: <20080225195402.M920@desktop> In-Reply-To: <47C37CAC.90806@freebsd.org> References: <20080225161855.M920@desktop> <47C37CAC.90806@freebsd.org>
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On Tue, 26 Feb 2008, David Xu wrote: > Jeff Roberson wrote: >> Also in the cpuset.diff at: >> >> http://people.freebsd.org/~jeff/cpuset.diff >> >> There is support for cpu topology aware scheduling. This allows the >> scheduler to know which cores are colocated on packages and what the cache >> arrangement between them is. >> >> We have seen big improvements in some workloads and some reduction in other >> workloads. However, I believe this should finally close the gap on the few >> benchmarks where ULE could trail 4BSD. Please prove me wrong if you can so >> I can continue to make ULE better. >> >> Right now the MD code is slightly lagging behind what the scheduler can >> utilize. If you have an interest in digging through processor >> documentation to write code to detect more information about the caches >> please contact me. I'd love some help. >> >> This code and the cpusets will likely be committed to 8.0 by the end of the >> week and then we'll discuss MFCs after some time to settle there. >> >> Thanks, >> Jeff > > FYI, sometimes ago, I have written some code to collect cpu topology > information according to vendor's specifications, it is only for x86. > each cpu just calls cpu_topology_update() at startup time, and the > information will be collected. > > http://people.freebsd.org/~davidxu/sched/ > > note that these code have not been updated for AMD's 4-core > package yet, I have not this cpu. Thanks David, I think our identcpu.c already detects this information. That's what I'm using. Although I assume that all cpus are identical and fall back on a flat topology if this isn't the case. I'd like to start including more cache information though. Jeff > > Regards, > David Xu > > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" >
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