ananicy recommendation
dim-geo opened this issue · 6 comments
Ananicy
I can just talk from my side and the expierence of the CachyOS User:
We are using at CachyOS ananicy-cpp as default enabled with the following Rules https://github.com/CachyOS/ananicy-rules and it is working very well with the BORE Scheduler.
On top we also add the "latency-nice" patchset (https://github.com/CachyOS/kernel-patches/blob/master/6.1/misc/0001-Add-latency-priority-for-CFS-class.patch) , Latency Nice is something equal as "nice" to for the scheduler latency.
Be aware that the latency nice implementation can be currently only used with ananicy-cpp. Ananicy has no implementation for this.
In my testings, benchmarks and user report the combination works very well.
BORE with some tweaked sysctl values does also bring a really good performance. So, the best way would be to test it on your own and enable/disable ananicy-cpp and check which one works better for you
I am on 5.15, will try those patches when I' ll upgrade.
Thanks for the suggestions!
Which sysctl values do you suggest to tweak?
I am on 5.15, will try those patches when I' ll upgrade. Thanks for the suggestions! Which sysctl values do you suggest to tweak?
Actually you can find a patch which includes the sysctl changes from @firelzrd .
He did also wrote a little ruby tool to test and switch them at runtime:
https://github.com/CachyOS/CachyOS-Settings/blob/master/usr/bin/tunecfs2
There are some values in which you can test.
BORE treats tasks to be "fair (in CFS way) if burst scores are same."
"Niceness" and "burst score" multipliers are both applied when incremental vruntime is calculated, and they follow the commutative law.
That means for example a task with +5 niceness and 0 burst score is granted basically the same CPU time as 0 niceness and +5 burst score.
Setting higher/lower niceness has basically the same effect as in CFS. But since burst scores usually move up and down dynamically depending on each task's recent behavior, the result of combined effects may vary.
Thanks for the info!
How much can burst score impact niceness?
Can it boost/de-prioritize a process of nice 0 from -20 up to +19?
Exactly. Yes.