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 12.6

(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 3,200
bash 118,863 1,417
osh-native 118,863 462
osh-nosouffle 118,863 411
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 7 4 3 9 2,698 Build.sh
osh-nosouffle 8 6 2 9 2,698 Build.sh
osh-cpython 286 267 19 22 2,698 Build.sh
dash 1 1 0 2 2,512 abuild
bash 3 3 0 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 7 3 9 2,512 abuild
osh-cpython 400 383 17 23 2,512 abuild
dash 7 6 1 2 20,489 configure
bash 15 15 1 4 20,489 configure
osh-native 41 30 11 22 20,489 configure
osh-nosouffle 44 33 11 23 20,489 configure
osh-cpython 1,873 1,848 25 44 20,489 configure
dash 18 16 2 2 69,779 configure-coreutils
bash 38 35 3 4 69,779 configure-coreutils
osh-native 145 124 21 52 69,779 configure-coreutils
osh-nosouffle 168 148 20 52 69,779 configure-coreutils
osh-cpython 5,469 5,406 62 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 6 0 9 2,029 configure-helper.sh
osh-nosouffle 6 5 1 9 2,029 configure-helper.sh
osh-cpython 280 267 14 22 2,029 configure-helper.sh
dash 1 0 1 2 1,733 functions
bash 2 2 1 3 1,733 functions
osh-native 6 5 1 8 1,733 functions
osh-nosouffle 7 6 1 9 1,733 functions
osh-cpython 271 251 20 21 1,733 functions
dash 4 3 1 2 9,661 ltmain.sh
bash 9 7 2 4 9,661 ltmain.sh
osh-native 20 15 5 16 9,661 ltmain.sh
osh-nosouffle 21 15 6 16 9,661 ltmain.sh
osh-cpython 895 870 25 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 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 1 2 8 1,679 t4014-format-patch.sh
osh-cpython 104 92 13 19 1,679 t4014-format-patch.sh
dash 1 0 1 2 3,123 t9300-fast-import.sh
bash 2 1 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 107 91 15 19 3,123 t9300-fast-import.sh
bash 7 5 2 3 5,160 test-cmd-util.sh
osh-native 18 13 5 13 5,160 test-cmd-util.sh
osh-nosouffle 18 15 3 13 5,160 test-cmd-util.sh
osh-cpython 819 805 13 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 31,596,863 2,698 Build.sh
osh-nosouffle 35,844,538 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,714,234 2,512 abuild
osh-nosouffle 52,275,041 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,142,274 20,489 configure
osh-nosouffle 263,054,817 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,400,999 69,779 configure-coreutils
osh-nosouffle 837,539,767 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,984,505 2,029 configure-helper.sh
osh-nosouffle 30,262,542 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,469,808 1,733 functions
osh-nosouffle 28,859,238 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,274,213 9,661 ltmain.sh
osh-nosouffle 112,484,887 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,062,614 1,679 t4014-format-patch.sh
osh-nosouffle 11,037,468 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 11,866,974 3,123 t9300-fast-import.sh
osh-nosouffle 13,017,411 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 96,179,657 5,160 test-cmd-util.sh
osh-nosouffle 112,286,676 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-4ce31e48
osh-native osh-76ca2808
osh-nosouffle osh-nosouffle-19c86e55
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-09__01-50-02.cachegrind.tsv
no-host.2025-12-09__01-50-02.times.csv