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 2,598
bash 118,863 1,232
osh-native 118,863 481
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 1 1 2 2,698 Build.sh
bash 3 1 2 3 2,698 Build.sh
osh-native 7 5 2 9 2,698 Build.sh
osh-nosouffle 8 2 6 9 2,698 Build.sh
osh-cpython 326 311 16 22 2,698 Build.sh
dash 2 2 0 2 2,512 abuild
bash 4 4 0 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 10 0 9 2,512 abuild
osh-cpython 460 437 23 22 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 17 15 2 4 20,489 configure
osh-native 39 29 11 22 20,489 configure
osh-nosouffle 43 31 11 23 20,489 configure
osh-cpython 2,133 2,086 46 44 20,489 configure
dash 23 20 3 2 69,779 configure-coreutils
bash 45 44 1 3 69,779 configure-coreutils
osh-native 135 107 28 52 69,779 configure-coreutils
osh-nosouffle 151 133 18 52 69,779 configure-coreutils
osh-cpython 6,316 6,224 92 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 6 0 8 2,029 configure-helper.sh
osh-nosouffle 7 4 3 9 2,029 configure-helper.sh
osh-cpython 314 291 23 21 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 3 3 8 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 315 291 24 21 1,733 functions
dash 4 4 1 2 9,661 ltmain.sh
bash 9 8 1 4 9,661 ltmain.sh
osh-native 19 14 5 15 9,661 ltmain.sh
osh-nosouffle 21 14 7 16 9,661 ltmain.sh
osh-cpython 1,013 991 22 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-native 4 1 3 8 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 114 90 24 19 1,679 t4014-format-patch.sh
dash 1 0 1 1 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 1 3 8 3,123 t9300-fast-import.sh
osh-cpython 121 102 20 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 17 11 6 12 5,160 test-cmd-util.sh
osh-nosouffle 18 13 5 13 5,160 test-cmd-util.sh
osh-cpython 943 913 30 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 31,595,752 2,698 Build.sh
osh-nosouffle 35,843,439 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,713,595 2,512 abuild
osh-nosouffle 52,278,477 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,139,847 20,489 configure
osh-nosouffle 263,052,030 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,356,388 69,779 configure-coreutils
osh-nosouffle 837,536,182 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,983,714 2,029 configure-helper.sh
osh-nosouffle 30,261,747 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,469,021 1,733 functions
osh-nosouffle 28,858,463 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,272,778 9,661 ltmain.sh
osh-nosouffle 112,483,444 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,062,147 1,679 t4014-format-patch.sh
osh-nosouffle 11,037,021 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 11,866,624 3,123 t9300-fast-import.sh
osh-nosouffle 13,016,815 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 96,177,443 5,160 test-cmd-util.sh
osh-nosouffle 112,284,733 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-c27df3c5
osh-native osh-591dd16e
osh-nosouffle osh-nosouffle-5564862e
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-08__20-00-57.cachegrind.tsv
no-host.2025-12-08__20-00-57.times.csv