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 2,581
bash 118,863 1,269
osh-native 118,863 445
osh-nosouffle 118,863 428
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 4 4 9 2,698 Build.sh
osh-nosouffle 8 6 2 9 2,698 Build.sh
osh-cpython 328 310 18 21 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 3 1 3 2,512 abuild
osh-native 10 9 1 9 2,512 abuild
osh-nosouffle 10 8 2 9 2,512 abuild
osh-cpython 453 429 24 22 2,512 abuild
dash 9 9 0 2 20,489 configure
bash 17 16 1 4 20,489 configure
osh-native 41 31 10 22 20,489 configure
osh-nosouffle 43 33 11 23 20,489 configure
osh-cpython 2,128 2,076 50 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 42 41 2 3 69,779 configure-coreutils
osh-native 149 133 16 52 69,779 configure-coreutils
osh-nosouffle 152 122 30 52 69,779 configure-coreutils
osh-cpython 6,414 6,338 75 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 7 5 2 9 2,029 configure-helper.sh
osh-cpython 321 294 27 21 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 7 5 2 8 1,733 functions
osh-nosouffle 7 4 3 9 1,733 functions
osh-cpython 312 287 26 21 1,733 functions
dash 4 4 1 2 9,661 ltmain.sh
bash 9 8 1 4 9,661 ltmain.sh
osh-native 20 15 5 16 9,661 ltmain.sh
osh-nosouffle 22 13 9 16 9,661 ltmain.sh
osh-cpython 1,049 1,018 31 30 9,661 ltmain.sh
dash 1 0 1 1 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-nosouffle 4 0 4 8 1,679 t4014-format-patch.sh
osh-native 4 3 1 8 1,679 t4014-format-patch.sh
osh-cpython 115 91 24 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 2 1 2 3 3,123 t9300-fast-import.sh
osh-native 4 2 2 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 3 2 8 3,123 t9300-fast-import.sh
osh-cpython 126 108 18 19 3,123 t9300-fast-import.sh
bash 8 6 2 3 5,160 test-cmd-util.sh
osh-native 18 13 4 12 5,160 test-cmd-util.sh
osh-nosouffle 19 17 2 13 5,160 test-cmd-util.sh
osh-cpython 931 899 31 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 31,600,273 2,698 Build.sh
osh-nosouffle 35,848,471 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,722,858 2,512 abuild
osh-nosouffle 52,279,615 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,143,090 20,489 configure
osh-nosouffle 263,061,803 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,386,156 69,779 configure-coreutils
osh-nosouffle 862,831,358 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,986,903 2,029 configure-helper.sh
osh-nosouffle 30,265,079 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,470,745 1,733 functions
osh-nosouffle 28,860,151 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,274,257 9,661 ltmain.sh
osh-nosouffle 112,484,762 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,064,775 1,679 t4014-format-patch.sh
osh-nosouffle 11,038,960 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 11,869,174 3,123 t9300-fast-import.sh
osh-nosouffle 13,019,517 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 96,185,343 5,160 test-cmd-util.sh
osh-nosouffle 112,289,238 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-e20e7fdf
osh-native osh-ed978781
osh-nosouffle osh-nosouffle-326ba449
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-14__11-23-34.cachegrind.tsv
no-host.2025-12-14__11-23-34.times.csv