-***transparent_hugepage=never*** do not scan for small pages to combine to hugepages. We have no issues with memory usage, spare us of this periodic jitter.
-***processor.max_cstate=1 idle=poll*** do not switch to CPU power saving modes (c-states). Just run all cores at full speed all the time (we do not care about energy during our tests).
-***nohz=on nohz_full=1-7*** disable houskeeping os ticks on our isolated benchmark cores. core 0 will handle these when needed.
-***isolcpus=1-7*** ignores cores 1 to 7 for scheduling processes (expect system processes that are bound to cores).
### Pin all other processes to core 0 (crgoups)
We want to isolate our measurements to cores 1 to 7 and use core 0 for all non benchmark related processes.
isolcpus does some of this during startup (TODO: see if there are issues with task migration if we use isolcpus),
however, we need to configure the system to schedule our threads specifically onto the isolated cores.
cgroups is a tool well suited for this. See the tutorial for further information: https://github.com/lpechacek/cpuset/blob/master/doc/tutorial.txt
isolcpus is often used for this, however, we found that it disables the scheduler from balancing tasks
between the isolated cores. A better approach is to use cgroups.
See the tutorial for further information: https://github.com/lpechacek/cpuset/blob/master/doc/tutorial.txt
Essentially, we can partition our cores into two isolated groups, then map all tasks that can be moved away from
our benchmark cores, to ensure low influence of background tasks. Cgroups also nicely interact with
the real time scheduler, as described here https://www.linuxjournal.com/article/10165, because
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@@ -196,6 +194,7 @@ echo "Some might fail because they can not be mapped (e.g. core specific timers
