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 2,591
bash 118,863 1,278
osh-native 118,863 438
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 2 1 3 2,698 Build.sh
osh-native 7 5 2 9 2,698 Build.sh
osh-nosouffle 8 6 2 9 2,698 Build.sh
osh-cpython 323 306 17 22 2,698 Build.sh
dash 2 2 0 2 2,512 abuild
bash 4 2 1 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 8 2 9 2,512 abuild
osh-cpython 449 424 25 22 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 17 16 1 4 20,489 configure
osh-nosouffle 42 28 14 23 20,489 configure
osh-native 43 32 11 22 20,489 configure
osh-cpython 2,152 2,116 34 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 42 39 3 4 69,779 configure-coreutils
osh-nosouffle 152 133 19 52 69,779 configure-coreutils
osh-native 156 126 30 52 69,779 configure-coreutils
osh-cpython 6,285 6,212 72 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 5 1 9 2,029 configure-helper.sh
osh-nosouffle 7 5 2 9 2,029 configure-helper.sh
osh-cpython 320 298 22 21 2,029 configure-helper.sh
dash 1 1 0 1 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 3 4 9 1,733 functions
osh-nosouffle 7 1 6 9 1,733 functions
osh-cpython 308 278 31 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 12 8 16 9,661 ltmain.sh
osh-nosouffle 21 13 7 16 9,661 ltmain.sh
osh-cpython 1,035 1,002 33 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 2 2 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 115 97 17 19 1,679 t4014-format-patch.sh
dash 1 0 1 1 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-native 4 2 2 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 16 12 4 12 5,160 test-cmd-util.sh
osh-nosouffle 18 16 2 13 5,160 test-cmd-util.sh
osh-cpython 921 894 27 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 31,596,838 2,698 Build.sh
osh-nosouffle 35,844,508 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,715,085 2,512 abuild
osh-nosouffle 52,275,010 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,142,249 20,489 configure
osh-nosouffle 263,054,760 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,401,001 69,779 configure-coreutils
osh-nosouffle 837,539,710 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,984,480 2,029 configure-helper.sh
osh-nosouffle 30,262,539 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,469,783 1,733 functions
osh-nosouffle 28,859,235 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,274,188 9,661 ltmain.sh
osh-nosouffle 112,484,830 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,062,589 1,679 t4014-format-patch.sh
osh-nosouffle 11,037,465 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 11,866,949 3,123 t9300-fast-import.sh
osh-nosouffle 13,017,354 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 96,179,632 5,160 test-cmd-util.sh
osh-nosouffle 112,286,563 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-1ba85473
osh-native osh-f8ebbfba
osh-nosouffle osh-nosouffle-ea4d9d67
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-12__16-38-17.cachegrind.tsv
no-host.2025-12-12__16-38-17.times.csv