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 12.8

(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 2,594
bash 118,863 1,275
osh-native 118,863 483
osh-nosouffle 118,863 453
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 4 3 9 2,698 Build.sh
osh-nosouffle 7 4 4 9 2,698 Build.sh
osh-cpython 324 302 22 22 2,698 Build.sh
dash 2 2 0 2 2,512 abuild
bash 4 4 0 3 2,512 abuild
osh-native 9 9 0 9 2,512 abuild
osh-nosouffle 10 8 2 9 2,512 abuild
osh-cpython 457 435 21 22 2,512 abuild
dash 9 9 0 2 20,489 configure
bash 17 15 2 4 20,489 configure
osh-native 39 28 11 22 20,489 configure
osh-nosouffle 42 34 8 23 20,489 configure
osh-cpython 2,110 2,071 37 44 20,489 configure
dash 23 22 1 2 69,779 configure-coreutils
bash 43 41 2 3 69,779 configure-coreutils
osh-native 135 108 27 51 69,779 configure-coreutils
osh-nosouffle 143 121 22 52 69,779 configure-coreutils
osh-cpython 6,238 6,153 85 91 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-native 6 3 3 9 2,029 configure-helper.sh
osh-nosouffle 7 5 2 9 2,029 configure-helper.sh
osh-cpython 315 288 26 22 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 9 1,733 functions
osh-nosouffle 7 3 4 9 1,733 functions
osh-cpython 309 288 21 21 1,733 functions
dash 4 4 1 2 9,661 ltmain.sh
bash 9 7 2 4 9,661 ltmain.sh
osh-native 19 10 9 15 9,661 ltmain.sh
osh-nosouffle 21 17 4 16 9,661 ltmain.sh
osh-cpython 1,017 986 31 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 3 1 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 114 89 25 19 1,679 t4014-format-patch.sh
dash 1 1 0 1 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-nosouffle 4 4 0 9 3,123 t9300-fast-import.sh
osh-native 4 3 1 8 3,123 t9300-fast-import.sh
osh-cpython 122 105 17 19 3,123 t9300-fast-import.sh
bash 8 6 1 3 5,160 test-cmd-util.sh
osh-native 17 10 6 13 5,160 test-cmd-util.sh
osh-nosouffle 18 12 6 13 5,160 test-cmd-util.sh
osh-cpython 912 878 34 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 31,597,785 2,698 Build.sh
osh-nosouffle 35,846,084 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,720,345 2,512 abuild
osh-nosouffle 52,277,203 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,141,148 20,489 configure
osh-nosouffle 263,059,920 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,384,750 69,779 configure-coreutils
osh-nosouffle 862,830,029 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,984,350 2,029 configure-helper.sh
osh-nosouffle 30,262,657 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,468,240 1,733 functions
osh-nosouffle 28,857,774 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,271,847 9,661 ltmain.sh
osh-nosouffle 112,482,434 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,062,209 1,679 t4014-format-patch.sh
osh-nosouffle 11,037,143 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 11,866,632 3,123 t9300-fast-import.sh
osh-nosouffle 13,017,069 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 96,183,140 5,160 test-cmd-util.sh
osh-nosouffle 112,287,083 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-30613852
osh-native osh-7c67e649
osh-nosouffle osh-nosouffle-2b64e724
host label host id
no-host no-host-bba74091

Raw Data

filename
no-host.2026-01-28__20-52-17.cachegrind.tsv
no-host.2026-01-28__20-52-17.times.csv