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 2,571
bash 118,863 1,236
osh-native 118,863 456
osh-nosouffle 118,863 432
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 6 2 9 2,698 Build.sh
osh-cpython 325 306 19 22 2,698 Build.sh
dash 2 2 0 2 2,512 abuild
bash 4 3 1 3 2,512 abuild
osh-native 9 5 4 9 2,512 abuild
osh-nosouffle 10 8 2 9 2,512 abuild
osh-cpython 460 443 16 22 2,512 abuild
dash 9 8 1 2 20,489 configure
bash 18 15 3 4 20,489 configure
osh-native 40 33 7 23 20,489 configure
osh-nosouffle 43 32 11 23 20,489 configure
osh-cpython 2,194 2,161 33 44 20,489 configure
dash 23 23 0 2 69,779 configure-coreutils
bash 43 41 2 3 69,779 configure-coreutils
osh-native 144 121 23 51 69,779 configure-coreutils
osh-nosouffle 149 127 22 52 69,779 configure-coreutils
osh-cpython 6,326 6,232 93 90 69,779 configure-coreutils
bash 3 3 0 3 2,029 configure-helper.sh
osh-native 6 4 2 9 2,029 configure-helper.sh
osh-nosouffle 7 3 4 9 2,029 configure-helper.sh
osh-cpython 323 306 18 21 2,029 configure-helper.sh
dash 1 1 1 2 1,733 functions
bash 3 3 0 3 1,733 functions
osh-native 6 4 2 9 1,733 functions
osh-nosouffle 7 5 2 9 1,733 functions
osh-cpython 315 291 24 21 1,733 functions
dash 5 4 1 2 9,661 ltmain.sh
bash 9 8 1 4 9,661 ltmain.sh
osh-native 22 16 6 16 9,661 ltmain.sh
osh-nosouffle 22 15 7 16 9,661 ltmain.sh
osh-cpython 1,026 1,001 25 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 3 1 7 1,679 t4014-format-patch.sh
osh-nosouffle 4 2 2 8 1,679 t4014-format-patch.sh
osh-cpython 118 96 22 19 1,679 t4014-format-patch.sh
dash 1 0 1 1 3,123 t9300-fast-import.sh
bash 3 2 1 3 3,123 t9300-fast-import.sh
osh-native 4 1 3 8 3,123 t9300-fast-import.sh
osh-nosouffle 5 3 1 8 3,123 t9300-fast-import.sh
osh-cpython 122 104 18 19 3,123 t9300-fast-import.sh
bash 8 7 1 3 5,160 test-cmd-util.sh
osh-native 17 14 3 13 5,160 test-cmd-util.sh
osh-nosouffle 19 13 6 13 5,160 test-cmd-util.sh
osh-cpython 917 884 33 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 31,546,205 2,698 Build.sh
osh-nosouffle 35,821,050 2,698 Build.sh
dash 7,346,197 2,512 abuild
bash 23,586,858 2,512 abuild
osh-native 44,753,722 2,512 abuild
osh-nosouffle 52,352,217 2,512 abuild
dash 55,988,490 20,489 configure
bash 166,013,802 20,489 configure
osh-native 220,967,111 20,489 configure
osh-nosouffle 253,098,637 20,489 configure
dash 161,016,284 69,779 configure-coreutils
bash 440,767,942 69,779 configure-coreutils
osh-native 745,446,074 69,779 configure-coreutils
osh-nosouffle 835,078,285 69,779 configure-coreutils
bash 22,799,636 2,029 configure-helper.sh
osh-native 25,918,249 2,029 configure-helper.sh
osh-nosouffle 30,228,836 2,029 configure-helper.sh
dash 4,811,799 1,733 functions
bash 15,312,098 1,733 functions
osh-native 24,491,284 1,733 functions
osh-nosouffle 28,908,097 1,733 functions
dash 24,904,718 9,661 ltmain.sh
bash 80,310,064 9,661 ltmain.sh
osh-native 96,376,003 9,661 ltmain.sh
osh-nosouffle 112,722,975 9,661 ltmain.sh
dash 3,294,377 1,679 t4014-format-patch.sh
osh-native 10,051,244 1,679 t4014-format-patch.sh
osh-nosouffle 11,029,698 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 11,850,268 3,123 t9300-fast-import.sh
osh-nosouffle 13,000,259 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 96,055,139 5,160 test-cmd-util.sh
osh-nosouffle 112,217,865 5,160 test-cmd-util.sh

Shell and Host Details

shell label shell id
bash bash-36833674
dash dash-cea41b3e
osh-cpython osh-b3ce1790
osh-native osh-5dbe9bcd
osh-nosouffle osh-nosouffle-76ff7df4
host label host id
no-host no-host-9c670df1

Raw Data

filename
no-host.2025-11-17__01-29-09.cachegrind.tsv
no-host.2025-11-17__01-29-09.times.csv