3 Replies Latest reply on Feb 23, 2018 6:13 AM by admmedlifer

    HPET on AMD Opteron(tm) Processor 6172?


      Hi all,


      We're attempting to build a real-time system using Scientific Linux 6.X, Linux Kernel version 3.0.80 patched with the RT patch version 108 on a machine with the following processors:


      [root@hephaestus ~]# lscpu

      Architecture:          x86_64

      CPU op-mode(s):        32-bit, 64-bit

      Byte Order:            Little Endian

      CPU(s):                24

      On-line CPU(s) list:   0-23

      Thread(s) per core:    1

      Core(s) per socket:    12

      Socket(s):             2

      NUMA node(s):          4

      Vendor ID:             AuthenticAMD

      CPU family:            16

      Model:                 9

      Model name:            AMD Opteron(tm) Processor 6172

      Stepping:              1

      CPU MHz:               2100.328

      BogoMIPS:              4199.65

      Virtualization:        AMD-V

      L1d cache:             64K

      L1i cache:             64K

      L2 cache:              512K

      L3 cache:              5118K

      NUMA node0 CPU(s):     0-11

      NUMA node1 CPU(s):     12-23

      NUMA node2 CPU(s):    

      NUMA node3 CPU(s):


      My question is about the HPET, high performance event timers and whether they are possible on this hardware. They don't seem to be activated, even though I was sure to set CONFIG_HIGH_RES_TIMERS=y in the .config file when compiling the kernel.


      cat /proc/timer_list shows pit where I would expect to see hpet, and individual CPU lapic timers have a resolution of  "999848 nsecs" instead of the "1 nsecs" I would expect to see. The one thing we've