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All daq nodes should run the cpu frequency governor in either "ondemand" or "performance" mode.

As of this writing (May 2, 2022) the daq node daq-xpp-cam02 is not running the cpu frequency governor in "performance" mode.
It appears to be running in "ondemand" mode, which  "tries to use the slowest speed as much as possible, but quickly switches up or down when needed."

The epix10a2m requires "performance" mode for correct operation.

Hi,
For example in /cds/group/pcds/dist/pds/boot/daq-det-pgp01 we have the following:
for f in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
  echo "performance" > $f
done
This is set for all the machines that are running an epix10ka2m:
daq-det-pgp01
daq-mec-pgp02
daq-mfx-pgp01
daq-xcs-pgp02
daq-xpp-pgp02
Dan

$ hostname
daq-xpp-cam02
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemandperformance
$

===========

$ hostname
daq-xpp-dss03
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
powersave
powersave
powersave
powersave
powersave
powersave
$

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On March 26, 2015, Chris Ford wrote:

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:

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To: pcds-daq-l
Subject: SXR: hyperthreading enabled on daq-sxr-cam02 and '03?
 
Folks,
 
While testing the Andor camera  I learned that some DAQ nodes were known to work better than others for this USB-based device.
Tomy writes, "One example I remember is that daq-sxr-cam01 was okay to run for hours, but daq-sxr-cam{02,03} would hang after some minutes."
Today I took a closer look, and I noticed that hyperthreading seems to be enabled on daq-sxr-cam02 and '03, where Andor fails.
Hyperthreading seems to be *disabled* on daq-sxr-cam01, where Andor runs well.