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 12.6

(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 3,317
bash 118,863 1,450
osh-native 118,863 561
osh-nosouffle 118,863 507
osh-cpython 118,863 12

Per-File Measurements

Time and Memory

shell label elapsed ms user ms sys ms max rss MB num lines filename
dash 1 1 0 2 2,698 Build.sh
bash 3 2 1 3 2,698 Build.sh
osh-native 6 3 4 9 2,698 Build.sh
osh-nosouffle 7 6 1 9 2,698 Build.sh
osh-cpython 277 265 12 22 2,698 Build.sh
dash 1 1 0 2 2,512 abuild
bash 3 2 1 3 2,512 abuild
osh-native 8 6 2 9 2,512 abuild
osh-nosouffle 9 8 1 9 2,512 abuild
osh-cpython 392 379 13 23 2,512 abuild
dash 7 5 2 2 20,489 configure
bash 15 14 1 4 20,489 configure
osh-native 35 29 7 23 20,489 configure
osh-nosouffle 38 33 5 23 20,489 configure
osh-cpython 1,841 1,818 22 44 20,489 configure
dash 18 18 0 2 69,779 configure-coreutils
bash 38 37 1 3 69,779 configure-coreutils
osh-native 113 91 22 52 69,779 configure-coreutils
osh-nosouffle 128 110 18 52 69,779 configure-coreutils
osh-cpython 5,231 5,178 50 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 5 4 1 9 2,029 configure-helper.sh
osh-nosouffle 6 4 2 9 2,029 configure-helper.sh
osh-cpython 271 258 12 22 2,029 configure-helper.sh
dash 1 0 1 2 1,733 functions
bash 2 1 1 3 1,733 functions
osh-native 5 4 1 9 1,733 functions
osh-nosouffle 6 5 1 9 1,733 functions
osh-cpython 260 249 11 21 1,733 functions
dash 4 4 0 2 9,661 ltmain.sh
bash 8 6 2 4 9,661 ltmain.sh
osh-native 17 15 3 16 9,661 ltmain.sh
osh-nosouffle 18 14 4 16 9,661 ltmain.sh
osh-cpython 885 864 21 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 3 2 1 8 1,679 t4014-format-patch.sh
osh-nosouffle 3 3 0 8 1,679 t4014-format-patch.sh
osh-cpython 95 81 13 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 2 2 0 3 3,123 t9300-fast-import.sh
osh-native 3 3 0 8 3,123 t9300-fast-import.sh
osh-nosouffle 3 2 1 8 3,123 t9300-fast-import.sh
osh-cpython 101 85 16 19 3,123 t9300-fast-import.sh
bash 7 6 1 3 5,160 test-cmd-util.sh
osh-native 15 10 5 13 5,160 test-cmd-util.sh
osh-nosouffle 17 15 2 13 5,160 test-cmd-util.sh
osh-cpython 798 778 20 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 31,595,428 2,698 Build.sh
osh-nosouffle 35,843,182 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,713,515 2,512 abuild
osh-nosouffle 52,278,158 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,139,507 20,489 configure
osh-nosouffle 263,055,842 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,359,389 69,779 configure-coreutils
osh-nosouffle 837,534,198 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,983,473 2,029 configure-helper.sh
osh-nosouffle 30,261,611 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,468,782 1,733 functions
osh-nosouffle 28,858,214 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,272,556 9,661 ltmain.sh
osh-nosouffle 112,483,368 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,061,854 1,679 t4014-format-patch.sh
osh-nosouffle 11,036,773 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 11,866,321 3,123 t9300-fast-import.sh
osh-nosouffle 13,016,718 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 96,177,344 5,160 test-cmd-util.sh
osh-nosouffle 112,284,485 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-dd7ecdd1
osh-native osh-d614bf01
osh-nosouffle osh-nosouffle-1a1b55a7
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-08__19-01-32.cachegrind.tsv
no-host.2025-12-08__19-01-32.times.csv