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 2,538
bash 118,863 1,239
osh-native 118,863 369
osh-nosouffle 118,863 342
osh-cpython 118,863 9

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 2 1 3 2,698 Build.sh
osh-nosouffle 9 7 2 9 2,698 Build.sh
osh-native 9 6 3 9 2,698 Build.sh
osh-cpython 347 327 20 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 2 1 3 2,512 abuild
osh-native 11 8 4 9 2,512 abuild
osh-nosouffle 12 9 3 9 2,512 abuild
osh-cpython 474 456 18 23 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 18 17 1 4 20,489 configure
osh-native 47 40 6 23 20,489 configure
osh-nosouffle 55 49 6 23 20,489 configure
osh-cpython 2,208 2,165 43 44 20,489 configure
dash 23 22 1 2 69,779 configure-coreutils
bash 43 42 1 4 69,779 configure-coreutils
osh-native 185 161 24 51 69,779 configure-coreutils
osh-nosouffle 197 170 27 52 69,779 configure-coreutils
osh-cpython 6,732 6,653 78 91 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-native 8 6 2 9 2,029 configure-helper.sh
osh-nosouffle 8 3 5 9 2,029 configure-helper.sh
osh-cpython 329 303 27 21 2,029 configure-helper.sh
dash 1 1 0 1 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 7 4 3 9 1,733 functions
osh-nosouffle 8 3 5 9 1,733 functions
osh-cpython 326 310 16 21 1,733 functions
dash 5 5 0 2 9,661 ltmain.sh
bash 10 8 2 4 9,661 ltmain.sh
osh-native 24 14 10 15 9,661 ltmain.sh
osh-nosouffle 25 14 11 16 9,661 ltmain.sh
osh-cpython 1,034 1,004 29 30 9,661 ltmain.sh
dash 1 1 0 1 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-nosouffle 5 3 2 8 1,679 t4014-format-patch.sh
osh-native 5 4 1 8 1,679 t4014-format-patch.sh
osh-cpython 125 104 21 19 1,679 t4014-format-patch.sh
dash 1 0 1 1 3,123 t9300-fast-import.sh
bash 3 1 1 3 3,123 t9300-fast-import.sh
osh-nosouffle 5 1 4 8 3,123 t9300-fast-import.sh
osh-native 5 2 3 8 3,123 t9300-fast-import.sh
osh-cpython 127 108 19 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 21 14 6 13 5,160 test-cmd-util.sh
osh-nosouffle 25 16 9 13 5,160 test-cmd-util.sh
osh-cpython 958 926 32 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 31,601,645 2,698 Build.sh
osh-nosouffle 35,849,924 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,724,206 2,512 abuild
osh-nosouffle 52,281,071 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,145,008 20,489 configure
osh-nosouffle 263,063,760 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,388,570 69,779 configure-coreutils
osh-nosouffle 862,833,860 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,988,197 2,029 configure-helper.sh
osh-nosouffle 30,266,488 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,472,100 1,733 functions
osh-nosouffle 28,861,614 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,275,707 9,661 ltmain.sh
osh-nosouffle 112,486,274 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 11,040,933 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 96,187,237 5,160 test-cmd-util.sh
osh-nosouffle 112,291,023 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-66762fb4
osh-native osh-4b3af450
osh-nosouffle osh-nosouffle-a7ecaee1
host label host id
no-host no-host-bba74091

Raw Data

filename
no-host.2026-01-26__05-21-13.cachegrind.tsv
no-host.2026-01-26__05-21-13.times.csv