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 3,268
bash 118,863 1,431
osh-native 118,863 524
osh-nosouffle 118,863 483
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 2 1 3 2,698 Build.sh
osh-native 6 4 3 9 2,698 Build.sh
osh-nosouffle 7 7 0 9 2,698 Build.sh
osh-cpython 285 266 19 22 2,698 Build.sh
dash 1 0 1 2 2,512 abuild
bash 3 2 1 3 2,512 abuild
osh-native 8 8 0 9 2,512 abuild
osh-nosouffle 9 8 1 9 2,512 abuild
osh-cpython 389 371 18 22 2,512 abuild
dash 7 7 0 2 20,489 configure
bash 15 14 1 4 20,489 configure
osh-native 36 28 8 23 20,489 configure
osh-nosouffle 40 31 9 23 20,489 configure
osh-cpython 1,861 1,838 23 44 20,489 configure
dash 18 16 2 2 69,779 configure-coreutils
bash 38 36 2 4 69,779 configure-coreutils
osh-native 126 110 15 52 69,779 configure-coreutils
osh-nosouffle 134 119 15 52 69,779 configure-coreutils
osh-cpython 5,404 5,363 41 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 5 1 9 2,029 configure-helper.sh
osh-cpython 271 258 13 22 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 2 2 0 3 1,733 functions
osh-native 6 4 2 9 1,733 functions
osh-nosouffle 6 4 2 9 1,733 functions
osh-cpython 264 244 20 21 1,733 functions
dash 4 2 2 2 9,661 ltmain.sh
bash 8 7 1 4 9,661 ltmain.sh
osh-native 18 12 6 16 9,661 ltmain.sh
osh-nosouffle 20 16 4 16 9,661 ltmain.sh
osh-cpython 884 870 13 30 9,661 ltmain.sh
dash 1 1 0 2 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-native 3 2 1 8 1,679 t4014-format-patch.sh
osh-nosouffle 3 2 1 8 1,679 t4014-format-patch.sh
osh-cpython 97 82 15 19 1,679 t4014-format-patch.sh
dash 1 0 1 2 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-native 3 1 3 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 1 2 8 3,123 t9300-fast-import.sh
osh-cpython 103 88 14 19 3,123 t9300-fast-import.sh
bash 7 7 0 3 5,160 test-cmd-util.sh
osh-native 15 12 3 13 5,160 test-cmd-util.sh
osh-nosouffle 18 13 5 13 5,160 test-cmd-util.sh
osh-cpython 802 786 16 28 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 31,530,021 2,698 Build.sh
osh-nosouffle 35,779,342 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,668,566 2,512 abuild
osh-nosouffle 52,229,054 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,613,636 20,489 configure
osh-nosouffle 252,519,615 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 747,276,883 69,779 configure-coreutils
osh-nosouffle 836,596,100 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,992,398 2,029 configure-helper.sh
osh-nosouffle 30,272,575 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,428,077 1,733 functions
osh-nosouffle 28,817,384 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,116,607 9,661 ltmain.sh
osh-nosouffle 112,325,729 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,044,456 1,679 t4014-format-patch.sh
osh-nosouffle 11,019,057 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 11,849,873 3,123 t9300-fast-import.sh
osh-nosouffle 12,999,809 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 96,107,429 5,160 test-cmd-util.sh
osh-nosouffle 112,212,965 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-9a9eec35
osh-native osh-5edea4ca
osh-nosouffle osh-nosouffle-117df458
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-12__21-52-48.cachegrind.tsv
no-host.2025-11-12__21-52-48.times.csv