>>> On 24.11.16 at 16:14, <dario.faggi...@citrix.com> wrote: > When dumping ACPI C states, here's how things look like for _all_ CPUs: > Nov 23 13:13:00.382134 (XEN) ==cpu3== > Nov 23 13:13:00.382157 (XEN) active state: C-1 > Nov 23 13:13:00.390096 (XEN) max_cstate: C7 > Nov 23 13:13:00.390125 (XEN) states: > Nov 23 13:13:00.390148 (XEN) C1: type[C1] latency[000] usage[00000000] > method[ HALT] duration[0] > Nov 23 13:13:00.398055 (XEN) C0: usage[00000000] duration[4229118701384] > Nov 23 13:13:00.398090 (XEN) PC2[0] PC3[0] PC6[0] PC7[0] > Nov 23 13:13:00.406088 (XEN) CC3[0] CC6[0] CC7[0] > > And I checked other runs, and it's the same everywhere. > > I remember that Jan suggested trying to pass max_cstate=1 to Xen at > boot. I was about to ask Ian to do that for this host, but it looks > like we're using only C0 and C1 already anyway.
This indeed looks surprising for a half way modern system - is the BIOS perhaps limiting C-states (maybe instructed to via BIOS setup)? Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
