4 ms·

It spawns a new process each time right? I would think that would but a cap on how accurate it can get. For my purposes I use it all the time though, quick and

It spawns a new process each time right? I would think that would but a cap on how accurate it can get. For my purposes I use it all the time though, quick and easy sanity-check.

forrestthewoods 2y ago
The issue is it runs a kajillion tests to try and be “statistical”. But there’s no good way to say “just run it for 5 seconds and give me the best answer you can”. It’s very much designed for nanosecond to low microsecond benchmarks. Trying to fight this is trying to smash a square peg through a round hole.
- gforce_de 2y ago
  At least it gives some numbers and point in a direction: $ hyperfine --warmup 3 './hello-world-bin-sh.sh' './hello-world-env-python3.py' Benchmark 1: ./hello-world-bin-sh.sh Time (mean ± σ): 1.3 ms ± 0.4 ms [User: 1.0 ms, System: 0.5 ms] ... Benchmark 2: ./hello-world-env-python3.py Time (mean ± σ): 43.1 ms ± 1.4 ms [User: 33.6 ms, System: 8.4 ms] ...
- PhilipRoman 2y ago
  I disagree that it is designed for nano/micro benchmarks. If you want that level of detail, you need to stay within a single process, pinned to a core which is isolated from scheduler. At least I found it almost impossible to benchmark assembly routines with it.
- sharkdp 2y ago
  > The issue is it runs a kajillion tests to try and be “statistical”. If you see any reason for putting “statistical” in quotes, please let us know. hyperfine does not run a lot of tests, but it does try to find outliers in your measurements. This is really valuable in some cases. For example: we can detect when the first run of your program takes much longer than the rest of the runs. We can then show you a warning to let you know that you probably want to either use some warmup runs, or a "--prepare" command to clean (OS) caches if you want a cold-cache benchmark. > But there’s no good way to say “just run it for 5 seconds and give me the best answer you can”. What is the "best answer you can"? > It’s very much designed for nanosecond to low microsecond benchmarks. Absolutely not. With hyperfine, you can not measure execution times in the "low microsecond" range, let alone nanosecond range. See also my other comment.
oguz-ismail 2y ago
It spawns a new shell for each run and subtracts the average shell startup time from final results. Too much noise
- PhilipRoman 2y ago
  The shell can be disabled, leaving just fork+exec
  - sharkdp 2y ago
    Yes. If you don't make use of shell builtins/syntax, you can use hyperfine's `--shell=none`/`-N` option to disable the intermediate shell.
    - oguz-ismail 2y ago
      You still need to quote the command though. `hyperfine -N ls "$dir"' won't work, you need `hyperfine -N "ls ${dir@Q}"' or something. It'd be better if you could specify commands like with `find -exec'.
      - PhilipRoman 2y ago
        Oh that sucks, I really hate when programs impose useless shell parsing instead of letting the user give an argument vector natively.
        sharkdp 2y ago
        I don't think it's useless. You can use hyperfine to run multiple benchmarks at the same time, to get a comparison between multiple tools. So if you want it to work without quotes, you need to (1) come up with a way to separate commands and (2) come up with a way to distinguish hyperfine arguments from command arguments. It's doable, but it's also not a great UX if you have to write something like hyperfine -N -- ls "$dir" \; my_ls "$dir"

It spawns a new process each time right? I would think that would but a cap on how accurate it can get. For my purposes I use it all the time though, quick and easy sanity-check.

forrestthewoods 2y ago

The issue is it runs a kajillion tests to try and be “statistical”. But there’s no good way to say “just run it for 5 seconds and give me the best answer you can”. It’s very much designed for nanosecond to low microsecond benchmarks. Trying to fight this is trying to smash a square peg through a round hole.

gforce_de 2y ago
At least it gives some numbers and point in a direction: $ hyperfine --warmup 3 './hello-world-bin-sh.sh' './hello-world-env-python3.py' Benchmark 1: ./hello-world-bin-sh.sh Time (mean ± σ): 1.3 ms ± 0.4 ms [User: 1.0 ms, System: 0.5 ms] ... Benchmark 2: ./hello-world-env-python3.py Time (mean ± σ): 43.1 ms ± 1.4 ms [User: 33.6 ms, System: 8.4 ms] ...
PhilipRoman 2y ago
I disagree that it is designed for nano/micro benchmarks. If you want that level of detail, you need to stay within a single process, pinned to a core which is isolated from scheduler. At least I found it almost impossible to benchmark assembly routines with it.
sharkdp 2y ago
> The issue is it runs a kajillion tests to try and be “statistical”. If you see any reason for putting “statistical” in quotes, please let us know. hyperfine does not run a lot of tests, but it does try to find outliers in your measurements. This is really valuable in some cases. For example: we can detect when the first run of your program takes much longer than the rest of the runs. We can then show you a warning to let you know that you probably want to either use some warmup runs, or a "--prepare" command to clean (OS) caches if you want a cold-cache benchmark. > But there’s no good way to say “just run it for 5 seconds and give me the best answer you can”. What is the "best answer you can"? > It’s very much designed for nanosecond to low microsecond benchmarks. Absolutely not. With hyperfine, you can not measure execution times in the "low microsecond" range, let alone nanosecond range. See also my other comment.

oguz-ismail 2y ago

It spawns a new shell for each run and subtracts the average shell startup time from final results. Too much noise

PhilipRoman 2y ago
The shell can be disabled, leaving just fork+exec
- sharkdp 2y ago
  Yes. If you don't make use of shell builtins/syntax, you can use hyperfine's `--shell=none`/`-N` option to disable the intermediate shell.
  - oguz-ismail 2y ago
    You still need to quote the command though. `hyperfine -N ls "$dir"' won't work, you need `hyperfine -N "ls ${dir@Q}"' or something. It'd be better if you could specify commands like with `find -exec'.
    - PhilipRoman 2y ago
      Oh that sucks, I really hate when programs impose useless shell parsing instead of letting the user give an argument vector natively.
      - sharkdp 2y ago
        I don't think it's useless. You can use hyperfine to run multiple benchmarks at the same time, to get a comparison between multiple tools. So if you want it to work without quotes, you need to (1) come up with a way to separate commands and (2) come up with a way to distinguish hyperfine arguments from command arguments. It's doable, but it's also not a great UX if you have to write something like hyperfine -N -- ls "$dir" \; my_ls "$dir"