Le 21/06/2012 21:24, Yinghai Lu a écrit : > On Wed, Jun 20, 2012 at 10:56 PM, Brice Goglin wrote: >>> I suspected that could be other problem. intel system before >>> sandbridge does not have IIO. >>> they will have ioh instead, and one ioh would connect to two cpu sockets. >>> but _PXM for root bus in dsdt only can return one value. Aka it is >>> acpi spec limitation. >> The machines I am talking about have two IOHs (one connected to each >> socket). I only have an old 2.6.27 boot log at hand, I'll ask my admins >> for more. Do you want the 2.6.27 dmesg anyway? >> > log from 2.6.27 should be good enough for this. > > BIOS _PXM return 0 for both pci root buses? > Here's dmesg. I can't say for sure whether _PXM returns 0 since I don't know how to read all this :) But Linux puts the first socket cpumap in /sys/bus/pci/devices/*/local_cpus (and that's wrong according to the motherboard manual and according to the performance we see). Brice