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 2,589
bash 118,863 1,266
osh-native 118,863 478
osh-nosouffle 118,863 430
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 1 1 2 2,698 Build.sh
bash 3 2 1 3 2,698 Build.sh
osh-native 7 3 4 9 2,698 Build.sh
osh-nosouffle 8 7 1 9 2,698 Build.sh
osh-cpython 322 297 25 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 2 1 3 2,512 abuild
osh-native 9 4 5 9 2,512 abuild
osh-nosouffle 10 6 4 9 2,512 abuild
osh-cpython 458 434 24 22 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 17 17 0 4 20,489 configure
osh-native 38 26 12 22 20,489 configure
osh-nosouffle 42 34 8 23 20,489 configure
osh-cpython 2,123 2,089 34 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 42 42 0 3 69,779 configure-coreutils
osh-native 138 111 27 52 69,779 configure-coreutils
osh-nosouffle 155 133 22 52 69,779 configure-coreutils
osh-cpython 6,272 6,186 85 90 69,779 configure-coreutils
bash 3 3 1 3 2,029 configure-helper.sh
osh-native 6 4 2 9 2,029 configure-helper.sh
osh-nosouffle 7 5 2 9 2,029 configure-helper.sh
osh-cpython 320 300 20 21 2,029 configure-helper.sh
dash 1 1 1 2 1,733 functions
bash 3 3 0 3 1,733 functions
osh-native 6 5 1 9 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 307 286 21 21 1,733 functions
dash 4 3 2 2 9,661 ltmain.sh
bash 9 7 2 4 9,661 ltmain.sh
osh-native 19 15 4 15 9,661 ltmain.sh
osh-nosouffle 21 16 5 16 9,661 ltmain.sh
osh-cpython 1,013 991 22 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 4 1 3 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 114 92 22 19 1,679 t4014-format-patch.sh
dash 1 1 0 1 3,123 t9300-fast-import.sh
bash 3 2 1 3 3,123 t9300-fast-import.sh
osh-native 4 1 3 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 3 1 8 3,123 t9300-fast-import.sh
osh-cpython 121 102 19 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 16 12 4 12 5,160 test-cmd-util.sh
osh-nosouffle 18 15 3 13 5,160 test-cmd-util.sh
osh-cpython 923 899 24 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 31,532,609 2,698 Build.sh
osh-nosouffle 35,781,917 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,672,180 2,512 abuild
osh-nosouffle 52,232,530 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,622,847 20,489 configure
osh-nosouffle 252,531,135 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 747,299,955 69,779 configure-coreutils
osh-nosouffle 836,628,944 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 26,012,938 2,029 configure-helper.sh
osh-nosouffle 30,300,096 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,429,953 1,733 functions
osh-nosouffle 28,819,265 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,119,764 9,661 ltmain.sh
osh-nosouffle 112,329,572 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,044,624 1,679 t4014-format-patch.sh
osh-nosouffle 11,019,233 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 11,850,015 3,123 t9300-fast-import.sh
osh-nosouffle 12,999,931 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 96,121,593 5,160 test-cmd-util.sh
osh-nosouffle 112,227,742 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-de05ba64
osh-native osh-fdc198ad
osh-nosouffle osh-nosouffle-1a676f68
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-14__20-15-36.cachegrind.tsv
no-host.2025-11-14__20-15-36.times.csv