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 2,595
bash 118,863 1,275
osh-native 118,863 465
osh-nosouffle 118,863 450
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 4 4 9 2,698 Build.sh
osh-cpython 329 304 25 22 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 4 0 3 2,512 abuild
osh-native 9 8 1 9 2,512 abuild
osh-nosouffle 10 9 1 9 2,512 abuild
osh-cpython 450 432 18 22 2,512 abuild
dash 9 9 0 2 20,489 configure
bash 17 14 3 4 20,489 configure
osh-native 40 32 8 22 20,489 configure
osh-nosouffle 42 30 12 23 20,489 configure
osh-cpython 2,156 2,112 44 44 20,489 configure
dash 23 21 2 2 69,779 configure-coreutils
bash 42 42 0 3 69,779 configure-coreutils
osh-native 141 110 31 52 69,779 configure-coreutils
osh-nosouffle 144 118 26 52 69,779 configure-coreutils
osh-cpython 6,295 6,209 86 91 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-nosouffle 7 5 1 9 2,029 configure-helper.sh
osh-native 7 2 5 9 2,029 configure-helper.sh
osh-cpython 321 303 19 21 2,029 configure-helper.sh
dash 1 1 0 2 1,733 functions
bash 3 2 1 3 1,733 functions
osh-native 6 3 4 9 1,733 functions
osh-nosouffle 6 3 4 9 1,733 functions
osh-cpython 308 291 17 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 16 4 16 9,661 ltmain.sh
osh-nosouffle 21 13 8 16 9,661 ltmain.sh
osh-cpython 1,025 995 30 30 9,661 ltmain.sh
dash 1 0 1 2 1,679 t4014-format-patch.sh
bash 2 1 1 3 1,679 t4014-format-patch.sh
osh-native 4 4 0 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 113 96 18 19 1,679 t4014-format-patch.sh
dash 1 1 0 2 3,123 t9300-fast-import.sh
bash 2 1 1 3 3,123 t9300-fast-import.sh
osh-native 4 2 2 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 1 3 8 3,123 t9300-fast-import.sh
osh-cpython 121 94 27 19 3,123 t9300-fast-import.sh
bash 8 8 0 3 5,160 test-cmd-util.sh
osh-native 17 12 5 13 5,160 test-cmd-util.sh
osh-nosouffle 18 14 4 13 5,160 test-cmd-util.sh
osh-cpython 920 888 32 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 31,530,711 2,698 Build.sh
osh-nosouffle 35,780,305 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,669,282 2,512 abuild
osh-nosouffle 52,230,016 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,614,326 20,489 configure
osh-nosouffle 252,520,578 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 747,277,573 69,779 configure-coreutils
osh-nosouffle 836,597,063 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,993,115 2,029 configure-helper.sh
osh-nosouffle 30,273,538 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,428,794 1,733 functions
osh-nosouffle 28,818,347 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,117,297 9,661 ltmain.sh
osh-nosouffle 112,326,692 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,045,173 1,679 t4014-format-patch.sh
osh-nosouffle 11,020,020 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 11,850,563 3,123 t9300-fast-import.sh
osh-nosouffle 13,000,772 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 96,108,119 5,160 test-cmd-util.sh
osh-nosouffle 112,213,964 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-adc7df46
osh-native osh-8b609277
osh-nosouffle osh-nosouffle-60ffbb6f
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-11__18-44-37.cachegrind.tsv
no-host.2025-11-11__18-44-37.times.csv