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 12.6

(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 2,604
bash 118,863 1,277
osh-native 118,863 485
osh-nosouffle 118,863 443
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 7 5 2 9 2,698 Build.sh
osh-nosouffle 8 7 1 9 2,698 Build.sh
osh-cpython 321 297 24 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 2 1 3 2,512 abuild
osh-native 9 8 1 9 2,512 abuild
osh-nosouffle 10 7 3 9 2,512 abuild
osh-cpython 457 436 21 22 2,512 abuild
dash 9 6 3 2 20,489 configure
bash 17 16 1 4 20,489 configure
osh-native 37 27 11 22 20,489 configure
osh-nosouffle 44 34 9 23 20,489 configure
osh-cpython 2,119 2,079 40 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 42 41 1 3 69,779 configure-coreutils
osh-native 137 111 26 52 69,779 configure-coreutils
osh-nosouffle 146 125 21 52 69,779 configure-coreutils
osh-cpython 6,206 6,124 81 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 4 3 9 2,029 configure-helper.sh
osh-nosouffle 7 3 3 9 2,029 configure-helper.sh
osh-cpython 319 299 20 21 2,029 configure-helper.sh
dash 1 0 1 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 5 1 8 1,733 functions
osh-nosouffle 6 5 1 9 1,733 functions
osh-cpython 307 287 20 21 1,733 functions
dash 4 4 0 2 9,661 ltmain.sh
bash 9 9 0 4 9,661 ltmain.sh
osh-native 19 15 4 15 9,661 ltmain.sh
osh-nosouffle 21 18 4 16 9,661 ltmain.sh
osh-cpython 1,019 990 29 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 1 3 8 1,679 t4014-format-patch.sh
osh-cpython 114 93 21 19 1,679 t4014-format-patch.sh
dash 1 1 0 1 3,123 t9300-fast-import.sh
bash 2 2 1 3 3,123 t9300-fast-import.sh
osh-native 4 1 3 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 4 0 8 3,123 t9300-fast-import.sh
osh-cpython 118 98 20 19 3,123 t9300-fast-import.sh
bash 8 6 2 3 5,160 test-cmd-util.sh
osh-native 16 12 4 12 5,160 test-cmd-util.sh
osh-nosouffle 19 12 7 13 5,160 test-cmd-util.sh
osh-cpython 943 913 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 31,592,089 2,698 Build.sh
osh-nosouffle 35,839,862 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,708,804 2,512 abuild
osh-nosouffle 52,273,698 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 221,047,091 20,489 configure
osh-nosouffle 263,041,028 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,361,104 69,779 configure-coreutils
osh-nosouffle 837,513,324 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,981,336 2,029 configure-helper.sh
osh-nosouffle 30,259,518 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,466,682 1,733 functions
osh-nosouffle 28,856,123 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,268,009 9,661 ltmain.sh
osh-nosouffle 112,478,140 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,060,966 1,679 t4014-format-patch.sh
osh-nosouffle 11,035,902 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 11,865,401 3,123 t9300-fast-import.sh
osh-nosouffle 13,015,730 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 96,171,424 5,160 test-cmd-util.sh
osh-nosouffle 112,278,602 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-f730b813
osh-native osh-0559a5e2
osh-nosouffle osh-nosouffle-6c4c38ca
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-01__01-06-25.cachegrind.tsv
no-host.2025-12-01__01-06-25.times.csv