OSH Parser Performance

We time $sh -n $file for various files under various shells, and repeat then run under cachegrind for stable metrics.

Source code: oils/benchmarks/osh-parser.sh

Raw files

Summary

Instructions Per Line (via cachegrind)

Lower numbers are generally better, but each shell recognizes a different language, and OSH uses a more thorough parsing algorithm. In thousands of "I refs".

shell label total lines thousand irefs per line
bash 118,863 7.3
dash 111,674 2.4
osh-native 118,863 11.0
osh-nosouffle 118,863 12.6

(zsh isn't measured because zsh -n unexpectedly forks.)

Average Parsing Rate, Measured on Two Machines (lines/ms)

Shell startup time is included in the elapsed time measurements, but long files are chosen to minimize its effect.

shell label total lines host no-host
dash 111,674 3,249
bash 118,863 1,414
osh-native 118,863 512
osh-nosouffle 118,863 467
osh-cpython 118,863 11

Per-File Measurements

Time and Memory

shell label elapsed ms user ms sys ms max rss MB num lines filename
dash 1 1 0 2 2,698 Build.sh
bash 3 3 0 3 2,698 Build.sh
osh-native 7 4 3 9 2,698 Build.sh
osh-nosouffle 7 5 2 9 2,698 Build.sh
osh-cpython 282 268 14 22 2,698 Build.sh
dash 1 1 0 2 2,512 abuild
bash 3 2 1 3 2,512 abuild
osh-native 9 7 1 9 2,512 abuild
osh-nosouffle 10 7 3 9 2,512 abuild
osh-cpython 404 382 22 23 2,512 abuild
dash 7 7 0 2 20,489 configure
bash 16 15 1 4 20,489 configure
osh-native 37 28 9 22 20,489 configure
osh-nosouffle 40 34 6 23 20,489 configure
osh-cpython 1,862 1,844 19 44 20,489 configure
dash 18 17 1 2 69,779 configure-coreutils
bash 38 37 1 4 69,779 configure-coreutils
osh-native 128 105 23 52 69,779 configure-coreutils
osh-nosouffle 140 123 17 52 69,779 configure-coreutils
osh-cpython 5,381 5,327 50 91 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-native 6 4 2 9 2,029 configure-helper.sh
osh-nosouffle 6 6 0 9 2,029 configure-helper.sh
osh-cpython 277 266 10 21 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 2 2 0 3 1,733 functions
osh-native 6 3 3 8 1,733 functions
osh-nosouffle 6 2 4 9 1,733 functions
osh-cpython 264 252 12 21 1,733 functions
dash 4 3 1 2 9,661 ltmain.sh
bash 8 8 0 4 9,661 ltmain.sh
osh-native 18 13 5 16 9,661 ltmain.sh
osh-nosouffle 20 17 3 16 9,661 ltmain.sh
osh-cpython 891 872 19 30 9,661 ltmain.sh
dash 1 0 1 2 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-native 3 3 0 8 1,679 t4014-format-patch.sh
osh-nosouffle 3 1 2 8 1,679 t4014-format-patch.sh
osh-cpython 98 89 9 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-native 4 4 0 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 1 3 8 3,123 t9300-fast-import.sh
osh-cpython 104 96 8 19 3,123 t9300-fast-import.sh
bash 7 7 0 3 5,160 test-cmd-util.sh
osh-native 16 11 5 13 5,160 test-cmd-util.sh
osh-nosouffle 18 15 3 13 5,160 test-cmd-util.sh
osh-cpython 809 790 19 29 5,160 test-cmd-util.sh

Instruction Counts

shell label irefs num lines filename
dash 6,684,258 2,698 Build.sh
bash 19,403,577 2,698 Build.sh
osh-native 31,592,106 2,698 Build.sh
osh-nosouffle 35,839,850 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,708,822 2,512 abuild
osh-nosouffle 52,273,687 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 221,047,054 20,489 configure
osh-nosouffle 263,041,016 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,361,067 69,779 configure-coreutils
osh-nosouffle 837,513,312 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,981,353 2,029 configure-helper.sh
osh-nosouffle 30,259,506 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,466,699 1,733 functions
osh-nosouffle 28,856,111 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,267,972 9,661 ltmain.sh
osh-nosouffle 112,478,128 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,060,983 1,679 t4014-format-patch.sh
osh-nosouffle 11,035,890 1,679 t4014-format-patch.sh
bash 11,082,677 1,679 t4014-format-patch.sh
dash 4,585,030 3,123 t9300-fast-import.sh
osh-native 11,865,391 3,123 t9300-fast-import.sh
osh-nosouffle 13,015,718 3,123 t9300-fast-import.sh
bash 16,659,503 3,123 t9300-fast-import.sh
bash 73,195,614 5,160 test-cmd-util.sh
osh-native 96,171,531 5,160 test-cmd-util.sh
osh-nosouffle 112,278,782 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-f2aedf63
osh-native osh-74cbb2a4
osh-nosouffle osh-nosouffle-e75e8aa3
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-04__21-44-37.cachegrind.tsv
no-host.2025-12-04__21-44-37.times.csv