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 2,604
bash 118,863 1,282
osh-native 118,863 494
osh-nosouffle 118,863 452
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 7 1 9 2,698 Build.sh
osh-cpython 321 298 23 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 3 3 0 3 2,512 abuild
osh-native 9 6 2 9 2,512 abuild
osh-nosouffle 10 7 2 9 2,512 abuild
osh-cpython 445 421 24 22 2,512 abuild
dash 9 7 2 2 20,489 configure
bash 17 17 0 4 20,489 configure
osh-native 37 25 12 22 20,489 configure
osh-nosouffle 40 33 8 23 20,489 configure
osh-cpython 2,089 2,049 38 44 20,489 configure
dash 23 22 1 2 69,779 configure-coreutils
bash 42 40 3 3 69,779 configure-coreutils
osh-native 132 105 26 52 69,779 configure-coreutils
osh-nosouffle 145 125 20 52 69,779 configure-coreutils
osh-cpython 6,121 6,047 74 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 4 2 9 2,029 configure-helper.sh
osh-nosouffle 7 4 3 9 2,029 configure-helper.sh
osh-cpython 312 297 15 21 2,029 configure-helper.sh
dash 1 1 1 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 4 2 8 1,733 functions
osh-nosouffle 7 4 3 9 1,733 functions
osh-cpython 307 288 20 21 1,733 functions
dash 4 3 1 2 9,661 ltmain.sh
bash 9 9 0 4 9,661 ltmain.sh
osh-native 20 18 2 15 9,661 ltmain.sh
osh-nosouffle 21 15 6 16 9,661 ltmain.sh
osh-cpython 1,003 974 29 30 9,661 ltmain.sh
dash 1 0 1 2 1,679 t4014-format-patch.sh
bash 2 2 0 3 1,679 t4014-format-patch.sh
osh-native 4 1 3 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 1 3 8 1,679 t4014-format-patch.sh
osh-cpython 110 91 20 19 1,679 t4014-format-patch.sh
dash 1 1 0 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 118 97 21 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 17 14 3 12 5,160 test-cmd-util.sh
osh-nosouffle 18 14 4 13 5,160 test-cmd-util.sh
osh-cpython 910 880 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 31,535,723 2,698 Build.sh
osh-nosouffle 35,785,404 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,675,907 2,512 abuild
osh-nosouffle 52,236,414 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,647,029 20,489 configure
osh-nosouffle 252,557,849 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 747,412,636 69,779 configure-coreutils
osh-nosouffle 836,744,281 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,946,888 2,029 configure-helper.sh
osh-nosouffle 30,224,500 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,432,760 1,733 functions
osh-nosouffle 28,822,152 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,130,100 9,661 ltmain.sh
osh-nosouffle 112,341,888 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,045,697 1,679 t4014-format-patch.sh
osh-nosouffle 11,020,610 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 11,850,501 3,123 t9300-fast-import.sh
osh-nosouffle 13,000,781 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 96,119,079 5,160 test-cmd-util.sh
osh-nosouffle 112,224,618 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-e00676df
osh-native osh-bf050521
osh-nosouffle osh-nosouffle-b9946a6d
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-26__00-55-08.cachegrind.tsv
no-host.2025-11-26__00-55-08.times.csv