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 11.1
osh-nosouffle 118,863 12.8

(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 2,590
bash 118,863 1,261
osh-native 118,863 455
osh-nosouffle 118,863 436
osh-cpython 118,863 10

Per-File Measurements

Time and Memory

shell label elapsed ms user ms sys ms max rss MB num lines filename
dash 2 2 0 2 2,698 Build.sh
bash 3 3 0 3 2,698 Build.sh
osh-native 7 5 2 9 2,698 Build.sh
osh-nosouffle 8 6 2 9 2,698 Build.sh
osh-cpython 328 306 22 21 2,698 Build.sh
dash 2 2 0 2 2,512 abuild
bash 4 3 1 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 7 3 9 2,512 abuild
osh-cpython 454 429 25 23 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 17 16 1 4 20,489 configure
osh-native 40 28 12 22 20,489 configure
osh-nosouffle 43 35 8 23 20,489 configure
osh-cpython 2,195 2,152 43 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 42 40 2 4 69,779 configure-coreutils
osh-native 147 120 27 51 69,779 configure-coreutils
osh-nosouffle 149 127 22 52 69,779 configure-coreutils
osh-cpython 6,271 6,187 81 91 69,779 configure-coreutils
bash 3 3 1 3 2,029 configure-helper.sh
osh-native 7 5 2 9 2,029 configure-helper.sh
osh-nosouffle 7 4 3 9 2,029 configure-helper.sh
osh-cpython 314 285 29 21 2,029 configure-helper.sh
dash 1 0 1 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 4 2 8 1,733 functions
osh-nosouffle 7 4 3 9 1,733 functions
osh-cpython 307 286 21 21 1,733 functions
dash 4 4 1 2 9,661 ltmain.sh
bash 9 9 0 4 9,661 ltmain.sh
osh-native 20 13 7 15 9,661 ltmain.sh
osh-nosouffle 22 19 3 16 9,661 ltmain.sh
osh-cpython 1,038 1,012 26 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 4 2 2 8 1,679 t4014-format-patch.sh
osh-nosouffle 4 1 3 8 1,679 t4014-format-patch.sh
osh-cpython 116 95 21 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 3 2 1 3 3,123 t9300-fast-import.sh
osh-native 4 2 2 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 5 0 8 3,123 t9300-fast-import.sh
osh-cpython 122 101 22 19 3,123 t9300-fast-import.sh
bash 8 6 2 3 5,160 test-cmd-util.sh
osh-native 17 14 3 12 5,160 test-cmd-util.sh
osh-nosouffle 19 14 5 13 5,160 test-cmd-util.sh
osh-cpython 927 899 28 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 31,601,607 2,698 Build.sh
osh-nosouffle 35,849,886 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,724,183 2,512 abuild
osh-nosouffle 52,281,021 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,144,442 20,489 configure
osh-nosouffle 263,063,194 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,387,500 69,779 configure-coreutils
osh-nosouffle 862,832,844 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,988,189 2,029 configure-helper.sh
osh-nosouffle 30,266,453 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,472,070 1,733 functions
osh-nosouffle 28,861,557 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,275,609 9,661 ltmain.sh
osh-nosouffle 112,486,176 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,066,000 1,679 t4014-format-patch.sh
osh-nosouffle 11,040,906 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 11,870,423 3,123 t9300-fast-import.sh
osh-nosouffle 13,020,859 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 96,186,863 5,160 test-cmd-util.sh
osh-nosouffle 112,290,649 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-f47da162
osh-native osh-5ce25b08
osh-nosouffle osh-nosouffle-422aa907
host label host id
no-host no-host-bba74091

Raw Data

filename
no-host.2026-01-26__03-58-56.cachegrind.tsv
no-host.2026-01-26__03-58-56.times.csv