diff --git a/.vscode/cspell.dictionaries/shell.wordlist.txt b/.vscode/cspell.dictionaries/shell.wordlist.txt index 16d7b25e997..95dea94a7cd 100644 --- a/.vscode/cspell.dictionaries/shell.wordlist.txt +++ b/.vscode/cspell.dictionaries/shell.wordlist.txt @@ -83,6 +83,8 @@ codespell commitlint dprint dtrace +flamegraph +flamegraphs gcov gmake grcov @@ -90,6 +92,7 @@ grep markdownlint rerast rollup +samply sed selinuxenabled sestatus diff --git a/src/uu/rm/BENCHMARKING.md b/src/uu/rm/BENCHMARKING.md new file mode 100644 index 00000000000..507906d497e --- /dev/null +++ b/src/uu/rm/BENCHMARKING.md @@ -0,0 +1,61 @@ + +# Benchmarking rm + +Run `cargo build --release` before benchmarking after you make a change! + +## Simple recursive rm + +- Get a large tree, for example linux kernel source tree. +- We'll need to pass a `--prepare` argument, since `rm` deletes the dir each time. +- Benchmark simple recursive rm with hyperfine: `hyperfine --prepare "cp -r tree tree-tmp" "target/release/coreutils rm -r tree-tmp"`. + +## Comparing with GNU rm + +Hyperfine accepts multiple commands to run and will compare them. To compare performance with GNU rm +duplicate the string you passed to hyperfine but remove the `target/release/coreutils` bit from it. + +Example: `hyperfine --prepare "cp -r tree tree-tmp" "target/release/coreutils rm -rf tree-tmp"` becomes +`hyperfine --prepare "cp -r tree tree-tmp" "target/release/coreutils rm -rf tree-tmp" "rm -rf tree-tmp"` +(This assumes GNU rm is installed as `rm`) + +This can also be used to compare with version of rm built before your changes to ensure your change does not regress this. + +Here is a `bash` script for doing this comparison: + +```shell +#!/bin/bash +cargo build --no-default-features --features rm --release +test_dir="$1" +hyperfine --prepare "cp -r $test_dir tmp_d" "rm -rf tmp_d" "target/release/coreutils rm -rf tmp_d" +``` + +## Checking system call count + +- Another thing to look at would be system calls count using strace (on linux) or equivalent on other operating systems. +- Example: `strace -c target/release/coreutils rm -rf tree` + +## Flamegraph + +### samply + +[samply](https://github.com/mstange/samply) is one option for simply creating flamegraphs. It uses the Firefox profiler as a UI. + +To install: +```bash +cargo install samply +``` + +To run: + +```bash +samply record target/release/coreutils rm -rf ../linux +``` + +### Cargo Flamegraph + +With Cargo Flamegraph you can easily make a flamegraph of `rm`: + +```shell +cargo flamegraph --cmd coreutils -- rm [additional parameters] +``` + diff --git a/src/uu/rm/benchmark.sh b/src/uu/rm/benchmark.sh new file mode 100755 index 00000000000..5feaea4e8f1 --- /dev/null +++ b/src/uu/rm/benchmark.sh @@ -0,0 +1,8 @@ +#!/bin/bash + +# Exit on any failures +set +x + +cargo build --no-default-features --features rm --release +test_dir="$1" +hyperfine --prepare "cp -r $test_dir tmp_d" "rm -rf tmp_d" "target/release/coreutils rm -rf tmp_d"