Hi Jan, "Jan Kara" <jack@xxxxxxx> writes: > Hi! > > On Tue 21-01-25 12:13:48, Andreas Hindborg via Lsf-pc wrote: >> I would like to propose that we have a session on Rust in the block >> layer again this year. Specifically I would like to discuss some rather >> puzzling results I observe when I benchmark the C and Rust null block >> drivers. I did a write up of the challenges I face at [1]. The >> observations are not tied to rust, they also manifest in the C driver. > > The results are indeed somewhat curious. One factor I didn't see addressed > in your blog is CPU scheduling. I've seen in the past cases where IO tasks > were getting migrated across cores leading to jumps in perfomance. Did you > try binding fio jobs to one CPU each? Yes, I am pinning the io jobs to cores with fio options `cpus_allowed=0-<jobs>` and `--cpus_allowed_policy=split` so I get 1 job per core. The kernel is configured with PREEMPT_NONE=y. Best regards, Andreas Hindborg
