On Wed, 2014-11-26 at 16:43 +0100, Laszlo Ersek wrote: > On 11/26/14 15:48, Laszlo Ersek wrote: > > Hi, > > > > On 11/13/14 19:42, Jordan Justen wrote: > >> On 2014-11-06 17:23:01, Fan, Jeff wrote: > >>> Chen, > >>> > >>> Thanks your contribution. I will check-in your patch if there is no > >>> further comments from other guys. > >>> > >>> Reviewed-by: Jeff Fan <jeff....@intel.com> > >> > >> Chen, > >> > >> I committed your series (r16345-r16371) for Jeff (to preserve the > >> separate patches). > >> > >> Thanks for all your work on this! > >> > >> Let me know if you are interested in working on some follow up MP > >> tasks. (I have 2 ideas. :) > >> > >> Jeff, > >> > >> Thanks for your review of this big series! > > > > I believe this series introduces an interesting performance regression, > > at least when it is part of OVMF and runs on qemu/kvm. > > > > Now the APs seem to be spinning infinitely, for example while the user > > is in the UEFI Setup utility. Before, there used to be no CPU load to > > speak of, while the user was in the UEFI Setup utility. > > > > The useless spinning is quite bad: > > - it hogs physical CPUs on the virtualization host for no good reason, > > - it wastes electricity (problem for both laptops and data centers). > > > > Can we make this feature dependent on a Feature PCD? At the moment I > > can't think of any workload I would run on the APs during runtime. > > No action needed; I realized there was a PCD already that allowed the > user to control this feature at build time -- I solved it for myself > with the attached patch.
hi, I think for all platform to simply modify the PcdCpuMaxLogicalProcessorNumber to one in UefiCpuPkg/UefiCpuPkg.dec is much easier to disable startup APs. Thanks, Chen > > Thank you > Laszlo > ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list edk2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel
