A benchmark utility for POSIX shell comparison
Usage: shellbench [options] files...
-s, --shell SHELL[,SHELL...] The shell(s) to run the benchmark. [default: sh]
-t, --time SECONDS Benchmark execution time. (SECONDS > 0) [default: 3]
-w, --warmup SECONDS Benchmark preparation time. (SECONDS > 0) [default: 1]
-c, --correct Enable correction mode to eliminate loop overhead.
-e, --error Display error details.
-h, --help You're looking at it.$ ./shellbench -s sh,bash,ksh,mksh,posh,zsh sample/count.sh sample/output.sh
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name sh bash ksh mksh posh zsh
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count.sh: posix 1,034,369 248,929 282,537 364,627 411,116 577,090
count.sh: typeset -i error 237,421 288,133 341,660 error 593,124
count.sh: increment error 272,415 443,765 350,265 error 835,077
output.sh: echo 279,335 121,104 375,175 179,903 201,718 59,138
output.sh: printf 277,989 118,461 209,123 180 179 63,644
output.sh: print error error 281,775 182,388 error 63,006
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* count: number of executions per secondfile: sample/count.sh
#!/bin/sh
setup() { i=1; }
cleanup() { :; }
#bench "posix"
@begin
i=$((i+1))
@end
#bench "typeset -i"
typeset -i i
@begin
i=$((i+1))
@end
#bench "increment"
typeset -i i
@begin
((i++))
@endfile: sample/output.sh
#!/bin/sh
#bench "echo"
@begin
echo "test"
@end
#bench "printf"
@begin
printf "test\n"
@end
#bench "print"
@begin
print "test"
@endDefine new benchmark
#bench NAMERepeatedly execute between @begin to @end, and count the number of executions.
@begin
echo "test"
@endInvoked before each benchmark.
Invoked after each benchmark.
| name | description | default |
|---|---|---|
| SHELLBENCH_SHELLS | The shell(s) to run the benchmark | sh |
| SHELLBENCH_BENCHMARK_TIME | Benchmark execution time | 3 |
| SHELLBENCH_WARMUP_TIME | Benchmark preparation time | 1 |
| SHELLBENCH_NAME_WIDTH | Display width of benchmark name | 30 |
| SHELLBENCH_COUNT_WIDTH | Display width of benchamrk count | 10 |
| SHELLBENCH_NULLLOOP_COUNT | null loop measurement |
ShellBench translates @begin and @end to loop as follows:
# From
@begin
echo "test"
@end
# Translate to
while __count=$(($__count+1)); do
echo "test"
doneThat is, during the benchmark time, not only echo but while, __ count=$(($__count+1)), count the number of times it is executed.
This loop will be killed by another process after benchmark time. Therefore, after @end is not executed.
Calculate the benchmark measurement results more strictly. This mode is suitable when the cost impact of the loop cannot be ignored.
Difference between default and modification mode
- Default mode: Measure
while,__count=$(($__count+1))and target code. - Correction mode: Measure only target code
Correction mode first measures the null loop and then eliminates the null loop measurement from the benchmark measurement.
# Null loop
while __count=$(($__count+1)); do
__CORRECTION_MODE=
doneAnd translates @begin and @end in correction mode as follows:
# From
@begin
echo "test"
@end
# Translate to
while __count=$(($__count+1)); do
__CORRECTION_MODE=
echo "test"
doneCompute a corrected value from the null loop execution count and the benchmark count.
Corrected count: B / ( 1.0 - ( B * ( 1.0 / A ) ) )
- A: null loop executed count
- B: benchmark count