Hello Henry,
1. Our sysadm said that there are kernel issues and "perf stat" cannot run on
these systems
Also RAPL throttling is on in the slow server. I am guessing this could
account for the throttled cpu speed. I am starting to google search to see
where this can be set from. Anyone out there know any good resources on RAPL
throttling or how to disable it?
Henry Poras <henry.poras@xxxxxxxxx> hat am 5. September 2017 um 06:39--
geschrieben:
Figured it was time to send the list an update.
1. Our sysadm said that there are kernel issues and "perf stat" cannot run on
these systems
2. I installed a slob instance on both a fast and slow server. There was no
way to stop our workload from running, but I ran slob multiple times, trying
to keep each run short (~3 minutes) so the underlying workload would not vary
much. Also tried running when the load was relatively low. All of the run
results were pretty consistent with one another. Configuring SLOB to run
strictly LIO, I saw ~4M lio/sec vs. 1.5M lio/sec
3. Our sysadm did get turbostat installed. What I take as the most important
output from that was:
slow: TSC_MHz - 2600 Bzy_MHz - 1200 PKG_% - 100%
fast: TSC_MHz - 2606 Bzy_MHz - 3110 PKG_% - 0%
So the clock speeds are nearly identical, ,but the running speeds when busy
are very different. Also RAPL throttling is on in the slow server. I am
guessing this could account for the throttled cpu speed. I am starting to
google search to see where this can be set from. Anyone out there know any
good resources on RAPL throttling or how to disable it?
Thanks.
Henry