ananicy-cpp and scx_bpfland, comparison and compatibility

[XZVB12]

Hello, I couldn’t find exact information about the compatibility of these two components and decided to ask here.
Should you use both or only one, will they conflict with each other ?
I ran Superposition Benchmark with two simultaneously and only with ananicy-cpp, the difference was at the level of inaccuracy.
SCX_SCHEDULER=scx_bpfland
SCX_FLAGS='-k -m performance'

If anyone can share their performance comparisons with scx vs ananicy-cpp I would be interested to know.
Thanks.

[arighi]

In general it is not recommended to run ananicy with bpfland, because bpfland is already prioritizing latency-sensitive tasks and ananicy can do the same (adjusting the task's niceness), so both effects can amplify such prioritization, leading to an excessive de-prioritization of cpu-intensive tasks.

However, that is not true in general, there might be some special cases where this extra prioritization can be beneficial. At the end, the best strategy is to test both ways and see which one works best for you. But keep in mind that you may hit some stall conditions with ananicy and bpfland running at the same time if you have lots of latency-sensitive and cpu-intensive tasks running at the same time.

Side note: I'd also recommend to drop -k from SCX_FLAGS if you're using a recent version of bpfland, as the kthread prioritization is not that useful with the latest changes in place.

[XZVB12]

Thanks for the reply.

I'd also recommend to drop -k from SCX_FLAGS

In my tests -k showed a performance improvement, but not much.
Today I finished re-testing, it seems ananicy-cpp still gives higher performance on my kernel and hardware.
That was one of the reasons for starting this discussion, I was wondering what the results for other systems/kernel were if someone would be willing to share them. I checked all scheduler that could be run and work stably
I’ve attached the test results in case anyone is interested. In the games, the situation is similar to.
I will leave this discussion open for ~ week (if you allow) in case someone wants to add information and then close it.
Linux Kernel: 6.12.9-1-MANJARO.
test.zip