Process: benchmark & improve `sysinfo` usage

[mempirate]

Context

Refreshing sysinfo can take a while (couple 10s of milliseconds, blocking) depending on the refresh info. We should double check that we can't slim it down the refresh kinds even more, based on the metrics we actually collect.

Would be nice to have benchmarks as well on Linux / MacOS, so we can document the collection cost.

[chahat-101]

Hi! I’d like to work on this.
I can add Criterion-based benchmarks for sysinfo refresh performance on Linux (and macOS if available), so we can measure and document the collection cost.
Once benchmarks are ready, we can see if the refresh kinds can be trimmed further.

[mempirate]

@chahat-101 great! Assigned you

[mempirate]

@chahat-101 are you still available to work on this?

[chahat-101]

I am working on this, sorry for the delay.

[mempirate]

Ah absolutely no worries. Just wanted to check if you were still planning to do this, as we could otherwise take over.

[chahat-101]

Apologies for the delay. I’m currently unable to continue with this, so please feel free to reassign it.

[tosynthegeek]

Hi @mempirate , I'd like to take this on.

Looking at ProcessCollector, the current RefreshKind setup has a few components worth profiling, particularly CpuRefreshKind::everything(), tasks, and disk usage. Rather than guessing which ones are expensive, my plan is to add Criterion benchmarks measuring collect() with different RefreshKind configurations, identify the main cost contributors, and then propose a slimmer default based on the actual data. I'll aim to cover both Linux and macOS where possible, and document the tradeoffs.

Could I be assigned to this?

[mempirate]

@tosynthegeek plan sounds solid. Assigned.

[tosynthegeek]

@tosynthegeek plan sounds solid. Assigned.

Hi @mempirate, I’ve opened a PR for this #67 . It includes the proposed changes along with benchmark results and a breakdown of RefreshKind costs across Linux and macOS.

I also included a follow-up question in the PR around whether CPU frequency metrics, would appreciate your review when you have time.