[hsbt]

On Windows, rss, maxrss and the RSS samples taken after each iteration are always 0, because there is no /proc, ps or getrusage to read them from.

This reports the working set and its peak from GetProcessMemoryInfo as RSS and MAXRSS. It also records the commit charge and its peak as commit_charge and peak_commit_charge, since private allocations on Windows show up there more than in the working set.

Only the benchmark process can read these between iterations and after its final GC, so this lives in the harness. The code is in lib/harness/windows_memory_counters.rb, which only Windows requires, so other platforms load nothing for it. It loads fiddle when the harness loads, because loading it later under Bundler resets Bundler between iterations.

Generated with Claude Code

[k0kubun]

Can we define Windows-only modules (and ideally methods as well) only when it's Windows? Unlike what's executed inside run_benchmarks.rb, what runs in harness/harness-common.rb directly impacts the benchmark target's performance, such as the size of allocated memory.

Combined with #549 (which may not need to be done inside harness-common.rb in the first place), I see a couple of modules and several methods that don't need to be defined in non-Windows platforms. Maybe we can define all of them under an is_windows guard.

[hsbt]

👌 I moved the memory counter code into a separate module and load it only on Windows.

[k0kubun]

Thanks 👍