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 2,599
bash 118,863 1,274
osh-native 118,863 473
osh-nosouffle 118,863 441
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 2 1 3 2,698 Build.sh
osh-native 7 6 1 9 2,698 Build.sh
osh-nosouffle 8 5 3 9 2,698 Build.sh
osh-cpython 324 301 23 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 4 0 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 6 4 9 2,512 abuild
osh-cpython 448 423 25 22 2,512 abuild
dash 9 7 2 2 20,489 configure
bash 17 14 3 4 20,489 configure
osh-native 39 27 12 23 20,489 configure
osh-nosouffle 42 33 9 23 20,489 configure
osh-cpython 2,143 2,108 35 44 20,489 configure
dash 23 22 1 2 69,779 configure-coreutils
bash 42 41 1 3 69,779 configure-coreutils
osh-native 137 112 25 52 69,779 configure-coreutils
osh-nosouffle 148 124 23 52 69,779 configure-coreutils
osh-cpython 6,260 6,166 93 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 7 3 4 9 2,029 configure-helper.sh
osh-nosouffle 7 5 2 9 2,029 configure-helper.sh
osh-cpython 319 292 26 21 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 3 1 2 3 1,733 functions
osh-native 6 6 0 9 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 308 286 22 21 1,733 functions
dash 4 4 0 2 9,661 ltmain.sh
bash 9 7 2 4 9,661 ltmain.sh
osh-native 20 13 7 16 9,661 ltmain.sh
osh-nosouffle 21 14 7 16 9,661 ltmain.sh
osh-cpython 1,020 991 27 30 9,661 ltmain.sh
dash 1 0 1 1 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-native 4 2 2 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 1 3 8 1,679 t4014-format-patch.sh
osh-cpython 114 98 16 19 1,679 t4014-format-patch.sh
dash 1 1 1 1 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-nosouffle 4 4 0 8 3,123 t9300-fast-import.sh
osh-native 4 0 4 8 3,123 t9300-fast-import.sh
osh-cpython 121 95 25 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 17 15 2 12 5,160 test-cmd-util.sh
osh-nosouffle 18 13 5 13 5,160 test-cmd-util.sh
osh-cpython 945 910 35 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 35,779,396 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,668,565 2,512 abuild
osh-nosouffle 52,229,107 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 252,519,642 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 836,596,127 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 30,272,629 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 112,325,783 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 12,999,863 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 112,213,019 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-50adb2c1
osh-native osh-bd4ca63a
osh-nosouffle osh-nosouffle-c090661b
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-12__21-59-08.cachegrind.tsv
no-host.2025-11-12__21-59-08.times.csv