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 2,559
bash 118,863 1,254
osh-native 118,863 449
osh-nosouffle 118,863 410
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 2 0 2 2,698 Build.sh
bash 3 2 1 3 2,698 Build.sh
osh-native 8 7 1 9 2,698 Build.sh
osh-nosouffle 8 6 2 9 2,698 Build.sh
osh-cpython 331 310 21 21 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 2 1 3 2,512 abuild
osh-native 9 7 2 9 2,512 abuild
osh-nosouffle 10 7 3 9 2,512 abuild
osh-cpython 462 434 28 22 2,512 abuild
dash 9 9 0 2 20,489 configure
bash 17 16 1 4 20,489 configure
osh-native 43 34 9 22 20,489 configure
osh-nosouffle 44 35 9 23 20,489 configure
osh-cpython 2,183 2,136 47 44 20,489 configure
dash 23 21 2 2 69,779 configure-coreutils
bash 42 42 0 3 69,779 configure-coreutils
osh-native 144 124 20 52 69,779 configure-coreutils
osh-nosouffle 163 136 27 52 69,779 configure-coreutils
osh-cpython 6,365 6,285 80 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 7 4 3 9 2,029 configure-helper.sh
osh-nosouffle 8 5 3 9 2,029 configure-helper.sh
osh-cpython 326 302 24 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 4 3 8 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 310 287 24 21 1,733 functions
dash 5 4 1 2 9,661 ltmain.sh
bash 10 8 2 4 9,661 ltmain.sh
osh-native 21 13 7 15 9,661 ltmain.sh
osh-nosouffle 22 15 7 16 9,661 ltmain.sh
osh-cpython 1,036 1,006 30 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 4 0 8 1,679 t4014-format-patch.sh
osh-cpython 123 104 19 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 3 2 1 3 3,123 t9300-fast-import.sh
osh-native 4 1 3 8 3,123 t9300-fast-import.sh
osh-nosouffle 5 4 1 8 3,123 t9300-fast-import.sh
osh-cpython 127 103 24 19 3,123 t9300-fast-import.sh
bash 8 6 2 3 5,160 test-cmd-util.sh
osh-native 18 14 4 13 5,160 test-cmd-util.sh
osh-nosouffle 19 15 4 13 5,160 test-cmd-util.sh
osh-cpython 932 901 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 31,600,658 2,698 Build.sh
osh-nosouffle 35,848,855 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,723,216 2,512 abuild
osh-nosouffle 52,279,999 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,143,502 20,489 configure
osh-nosouffle 263,062,187 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,386,568 69,779 configure-coreutils
osh-nosouffle 862,831,742 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,987,261 2,029 configure-helper.sh
osh-nosouffle 30,264,532 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,471,103 1,733 functions
osh-nosouffle 28,860,535 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,274,669 9,661 ltmain.sh
osh-nosouffle 112,485,146 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,065,133 1,679 t4014-format-patch.sh
osh-nosouffle 11,039,966 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 11,869,559 3,123 t9300-fast-import.sh
osh-nosouffle 13,019,901 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 96,185,755 5,160 test-cmd-util.sh
osh-nosouffle 112,289,622 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-4f606418
osh-native osh-2df97637
osh-nosouffle osh-nosouffle-36ea5c6b
host label host id
no-host no-host-bba74091

Raw Data

filename
no-host.2025-12-22__05-39-26.cachegrind.tsv
no-host.2025-12-22__05-39-26.times.csv