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 12.5

(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 3,050
bash 118,863 1,280
osh-native 118,863 506
osh-nosouffle 118,863 437
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 2 1 1 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 6 1 9 2,698 Build.sh
osh-cpython 291 274 17 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 3 1 3 2,512 abuild
osh-native 9 7 1 9 2,512 abuild
osh-nosouffle 9 6 3 9 2,512 abuild
osh-cpython 416 404 12 23 2,512 abuild
dash 8 7 1 2 20,489 configure
bash 16 16 0 4 20,489 configure
osh-native 37 32 5 23 20,489 configure
osh-nosouffle 42 36 6 23 20,489 configure
osh-cpython 1,883 1,854 29 44 20,489 configure
dash 18 18 0 2 69,779 configure-coreutils
bash 44 43 1 4 69,779 configure-coreutils
osh-native 130 107 23 52 69,779 configure-coreutils
osh-nosouffle 156 136 20 52 69,779 configure-coreutils
osh-cpython 5,501 5,439 59 91 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-native 6 5 1 9 2,029 configure-helper.sh
osh-nosouffle 6 4 2 9 2,029 configure-helper.sh
osh-cpython 285 271 14 22 2,029 configure-helper.sh
dash 1 1 1 1 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 3 3 9 1,733 functions
osh-nosouffle 6 6 0 9 1,733 functions
osh-cpython 290 273 17 21 1,733 functions
dash 4 3 1 2 9,661 ltmain.sh
bash 9 9 0 4 9,661 ltmain.sh
osh-native 18 13 6 16 9,661 ltmain.sh
osh-nosouffle 20 17 3 16 9,661 ltmain.sh
osh-cpython 905 888 17 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 7 1,679 t4014-format-patch.sh
osh-nosouffle 3 1 2 8 1,679 t4014-format-patch.sh
osh-cpython 131 116 15 19 1,679 t4014-format-patch.sh
dash 1 1 0 1 3,123 t9300-fast-import.sh
bash 3 3 0 3 3,123 t9300-fast-import.sh
osh-native 4 3 1 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 3 1 8 3,123 t9300-fast-import.sh
osh-cpython 110 92 18 19 3,123 t9300-fast-import.sh
bash 7 6 1 3 5,160 test-cmd-util.sh
osh-native 16 12 4 12 5,160 test-cmd-util.sh
osh-nosouffle 18 16 2 13 5,160 test-cmd-util.sh
osh-cpython 823 801 22 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 31,530,282 2,698 Build.sh
osh-nosouffle 35,779,592 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,668,827 2,512 abuild
osh-nosouffle 52,229,331 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,613,896 20,489 configure
osh-nosouffle 252,519,865 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 747,277,144 69,779 configure-coreutils
osh-nosouffle 836,596,347 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,992,659 2,029 configure-helper.sh
osh-nosouffle 30,272,849 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,428,338 1,733 functions
osh-nosouffle 28,817,661 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,116,868 9,661 ltmain.sh
osh-nosouffle 112,325,979 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,044,723 1,679 t4014-format-patch.sh
osh-nosouffle 11,019,340 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 11,850,140 3,123 t9300-fast-import.sh
osh-nosouffle 13,000,065 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 96,107,706 5,160 test-cmd-util.sh
osh-nosouffle 112,213,152 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-8b0272c5
osh-native osh-291bffd8
osh-nosouffle osh-nosouffle-283bbfaf
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-08__07-07-14.cachegrind.tsv
no-host.2025-11-08__07-07-14.times.csv