Wei Huang
2011-Jun-23 22:51 UTC
[Xen-devel] [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
Hi, The following two patches enable core-pair topology detection for AMD CPUs. The main idea is to record compute unit information into cpuinfo_x86 and use it when building sibling map. The sibling map will be used by Xen credit scheduler to coordinate VCPU scheduling in a fashion similar to SMT. This code is very similar to upstream Linux kernel. Regarding the performance improvement, I saw ~8% improvement running kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay benchmark using this patch and he saw ~5% improvement. No perf degradation was seen so far. Please review. Thanks, -Wei _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jan Beulich
2011-Jun-27 08:58 UTC
[Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
>>> On 24.06.11 at 00:51, Wei Huang <wei.huang2@amd.com> wrote: > Hi, > > The following two patches enable core-pair topology detection for AMD > CPUs. The main idea is to record compute unit information into > cpuinfo_x86 and use it when building sibling map. The sibling map will > be used by Xen credit scheduler to coordinate VCPU scheduling in a > fashion similar to SMT. This code is very similar to upstream Linux kernel. > > Regarding the performance improvement, I saw ~8% improvement running > kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay > benchmark using this patch and he saw ~5% improvement. No perf > degradation was seen so far. > > Please review.Apart from some indentation issues these look fine to me. Jan> Thanks, > -Wei_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Wei Huang
2011-Jun-27 17:26 UTC
[Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
Thanks, Jan and George. I attach the latest version which fixes the indentation issues. -Wei On 06/27/2011 03:58 AM, Jan Beulich wrote:>>>> On 24.06.11 at 00:51, Wei Huang<wei.huang2@amd.com> wrote: >> Hi, >> >> The following two patches enable core-pair topology detection for AMD >> CPUs. The main idea is to record compute unit information into >> cpuinfo_x86 and use it when building sibling map. The sibling map will >> be used by Xen credit scheduler to coordinate VCPU scheduling in a >> fashion similar to SMT. This code is very similar to upstream Linux kernel. >> >> Regarding the performance improvement, I saw ~8% improvement running >> kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay >> benchmark using this patch and he saw ~5% improvement. No perf >> degradation was seen so far. >> >> Please review. > Apart from some indentation issues these look fine to me. > > Jan > >> Thanks, >> -Wei > > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jan Beulich
2011-Jun-28 07:38 UTC
[Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
>>> On 27.06.11 at 19:26, Wei Huang <wei.huang2@amd.com> wrote: > Thanks, Jan and George. I attach the latest version which fixes the > indentation issues.Acked-by: Jan Beulich <jbeulich@novell.com>> > -Wei > > > On 06/27/2011 03:58 AM, Jan Beulich wrote: >>>>> On 24.06.11 at 00:51, Wei Huang<wei.huang2@amd.com> wrote: >>> Hi, >>> >>> The following two patches enable core-pair topology detection for AMD >>> CPUs. The main idea is to record compute unit information into >>> cpuinfo_x86 and use it when building sibling map. The sibling map will >>> be used by Xen credit scheduler to coordinate VCPU scheduling in a >>> fashion similar to SMT. This code is very similar to upstream Linux kernel. >>> >>> Regarding the performance improvement, I saw ~8% improvement running >>> kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay >>> benchmark using this patch and he saw ~5% improvement. No perf >>> degradation was seen so far. >>> >>> Please review. >> Apart from some indentation issues these look fine to me. >> >> Jan >> >>> Thanks, >>> -Wei >> >> >>_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
George Dunlap
2011-Jun-28 08:51 UTC
[Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
On Mon, 2011-06-27 at 18:26 +0100, Wei Huang wrote:> Thanks, Jan and George. I attach the latest version which fixes the > indentation issues.Assuming the patch has the same effect on the scheduling, my previous ack-effects-on-the-schedulers stands: Acked-by: George Dunlap <george.dunlap@eu.citrix.com>> > -Wei > > > On 06/27/2011 03:58 AM, Jan Beulich wrote: > >>>> On 24.06.11 at 00:51, Wei Huang<wei.huang2@amd.com> wrote: > >> Hi, > >> > >> The following two patches enable core-pair topology detection for AMD > >> CPUs. The main idea is to record compute unit information into > >> cpuinfo_x86 and use it when building sibling map. The sibling map will > >> be used by Xen credit scheduler to coordinate VCPU scheduling in a > >> fashion similar to SMT. This code is very similar to upstream Linux kernel. > >> > >> Regarding the performance improvement, I saw ~8% improvement running > >> kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay > >> benchmark using this patch and he saw ~5% improvement. No perf > >> degradation was seen so far. > >> > >> Please review. > > Apart from some indentation issues these look fine to me. > > > > Jan > > > >> Thanks, > >> -Wei > > > > > > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
George Dunlap
2011-Oct-21 10:31 UTC
Re: [Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
Sorry for the late request -- should these patches be back-ported to 4.1.2? Otherwise anyone using AMD Magny-cours may have a significant performance hit when using 4.1. -George On Mon, Jun 27, 2011 at 6:26 PM, Wei Huang <wei.huang2@amd.com> wrote:> Thanks, Jan and George. I attach the latest version which fixes the > indentation issues. > > -Wei > > > On 06/27/2011 03:58 AM, Jan Beulich wrote: >>>>> >>>>> On 24.06.11 at 00:51, Wei Huang<wei.huang2@amd.com> wrote: >>> >>> Hi, >>> >>> The following two patches enable core-pair topology detection for AMD >>> CPUs. The main idea is to record compute unit information into >>> cpuinfo_x86 and use it when building sibling map. The sibling map will >>> be used by Xen credit scheduler to coordinate VCPU scheduling in a >>> fashion similar to SMT. This code is very similar to upstream Linux >>> kernel. >>> >>> Regarding the performance improvement, I saw ~8% improvement running >>> kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay >>> benchmark using this patch and he saw ~5% improvement. No perf >>> degradation was seen so far. >>> >>> Please review. >> >> Apart from some indentation issues these look fine to me. >> >> Jan >> >>> Thanks, >>> -Wei >> >> >> > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel