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 2,576
bash 118,863 1,236
osh-nosouffle 118,863 452
osh-native 118,863 451
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 4 3 9 2,698 Build.sh
osh-nosouffle 8 4 4 9 2,698 Build.sh
osh-cpython 327 301 26 21 2,698 Build.sh
dash 2 1 1 2 2,512 abuild
bash 4 3 1 3 2,512 abuild
osh-native 9 7 2 9 2,512 abuild
osh-nosouffle 10 6 4 9 2,512 abuild
osh-cpython 447 422 25 22 2,512 abuild
dash 9 9 0 2 20,489 configure
bash 17 15 2 4 20,489 configure
osh-native 40 30 10 22 20,489 configure
osh-nosouffle 42 35 7 23 20,489 configure
osh-cpython 2,173 2,129 44 44 20,489 configure
dash 23 22 1 2 69,779 configure-coreutils
bash 45 42 3 4 69,779 configure-coreutils
osh-nosouffle 142 124 18 52 69,779 configure-coreutils
osh-native 149 124 25 52 69,779 configure-coreutils
osh-cpython 6,310 6,238 72 91 69,779 configure-coreutils
bash 3 2 1 3 2,029 configure-helper.sh
osh-native 6 4 2 9 2,029 configure-helper.sh
osh-nosouffle 7 4 3 9 2,029 configure-helper.sh
osh-cpython 321 299 22 21 2,029 configure-helper.sh
dash 1 1 1 1 1,733 functions
bash 3 1 1 3 1,733 functions
osh-native 6 3 3 8 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 310 287 24 21 1,733 functions
dash 4 3 1 2 9,661 ltmain.sh
bash 9 8 1 4 9,661 ltmain.sh
osh-native 20 17 3 15 9,661 ltmain.sh
osh-nosouffle 21 14 7 16 9,661 ltmain.sh
osh-cpython 1,015 989 26 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-native 4 1 3 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 3 1 8 1,679 t4014-format-patch.sh
osh-cpython 115 99 16 19 1,679 t4014-format-patch.sh
dash 1 0 1 2 3,123 t9300-fast-import.sh
bash 2 1 2 3 3,123 t9300-fast-import.sh
osh-native 4 3 1 8 3,123 t9300-fast-import.sh
osh-nosouffle 4 2 2 8 3,123 t9300-fast-import.sh
osh-cpython 121 103 18 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 17 9 8 12 5,160 test-cmd-util.sh
osh-nosouffle 18 17 1 13 5,160 test-cmd-util.sh
osh-cpython 933 908 25 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 31,592,872 2,698 Build.sh
osh-nosouffle 35,841,524 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,711,283 2,512 abuild
osh-nosouffle 52,275,356 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 231,135,338 20,489 configure
osh-nosouffle 263,051,655 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 748,351,946 69,779 configure-coreutils
osh-nosouffle 837,525,818 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,982,345 2,029 configure-helper.sh
osh-nosouffle 30,260,508 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,467,657 1,733 functions
osh-nosouffle 28,857,129 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,270,285 9,661 ltmain.sh
osh-nosouffle 112,481,188 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,061,257 1,679 t4014-format-patch.sh
osh-nosouffle 11,036,213 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 11,865,685 3,123 t9300-fast-import.sh
osh-nosouffle 13,016,161 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 96,174,940 5,160 test-cmd-util.sh
osh-nosouffle 112,281,859 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-ce2895f8
osh-native osh-fdd6ae97
osh-nosouffle osh-nosouffle-fe684795
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-12-06__02-20-11.cachegrind.tsv
no-host.2025-12-06__02-20-11.times.csv