Subtract out gc time?

[DaveBarton]

Would it help to subtract out the gc time, at least optionally? E.g. instead of just using getCPUTime, use mutator_cpu_ns and mutator_elapsed_ns:

import GHC.Stats (RTSStats, getRTSStats, getRTSStatsEnabled, mutator_cpu_ns, mutator_elapsed_ns)
import System.CPUTime (getCPUTime)

[Bodigrim]

I'm open to extend TimeMode with more options.

[Bodigrim]

Let me transfer the issue to tasty-bench repo, because extending TimeMode is a prerequisite for tasty-bench-fit to get other flavours.

[Bodigrim]

It is easy to extend TimeMode with additional constructors, but it is technically a breaking change, and we just bumped the major version not that long ago.

I can imagine us adding more and more TimeModes over the time, I'd like us to have a strategy to avoid breakage. Maybe hide the actual constructors and provide only a set of pattern synonyms?..

[DaveBarton]

I don't need this immediately & I don't have time to work on details now (will be busy with my paying job for a while, sadly). I mostly meant it as a design question for tasty-bench-fit, since it seemed the biggest problem with that is inconsistent results due to gc. If that's the case, would subtracting out gc time improve the usefulness of tasty-bench-fit significantly?