Chet Ramey (<chet.ra...@case.edu>) wrote: > It's in CWRU/CWRU.chlog in the development distributions >
I am sorry but I have been unable to find either the source code or the change log, either at the university site or by looking with google. However, I have made some tests. Yes, the deeper internal delay with arguments have been removed. Running this code (from https://unix.stackexchange.com/q/462084/265604): #!/bin/bash -- TIMEFORMAT='real: %R' f1 () { :; } f2 () { echo ' args = '"$#"; printf '1 function no args yes '; time for ((i=1;i<$n;i++)); do : ; done printf '2 function yes args yes '; time for ((i=1;i<$n;i++)); do f1 ; done set -- printf '3 function yes args no '; time for ((i=1;i<$n;i++)); do f1 ; done echo } main () { set -- $(seq $m) f2 "" f2 "$@" } n=1000; m=20000; main Which had a 20 seconds delay on the second call with arguments (old results): args = 1 1 function no args yes real: 0.012 2 function yes args yes real: 0.033 3 function yes args no real: 0.024 args = 20000 1 function no args yes real: 0.011 2 function yes args yes real: 20.446 3 function yes args no real: 0.021 Has almost removed the *reported *delay (as ksh does): b5b2sh ./script # bash beta 2 args = 1 1 function no args yes real: 0.026 2 function yes args yes real: 0.053 3 function yes args no real: 0.051 args = 20000 1 function no args yes real: 0.022 2 function yes args yes real: 0.052 3 function yes args no real: 0.046 However, the delay is still there, just not reported. Time the whole script to get: time b5b2sh ./script real 0m32.242s The delay has actually increased to 32 seconds, while ksh is able to get: time ksh ./script real 0m0.137s That's 32.242 / 0.137 = 235.343 times longer. It seems that the delay has just moved from the deep internal shuffling of arguments to the phases of creating (and, now also, erasing) the arguments. bash b5b2sh ksh set arguments 0.110 7.404 0.030 args = 1 1 function no args yes 0.014 0.025 0.020 2 function yes args yes 0.027 0.055 0.020 unset arguments 0.000 0.000 0.000 3 function yes args no 0.024 0.053 0.020 call function no args 0.080 5.207 0.070 args = 20000 1 function no args yes 0.011 0.026 0.000 2 function yes args yes 20.430 0.055 0.010 unset arguments 0.003 4.973 0.000 3 function yes args no 0.020 0.048 0.010 call function with args 20.578 23.530 0.040 total 20.788s 41.128s 0.151 It seems odd that now calling the function without arguments takes 5.207 seconds and that the un-setting (set --) the arguments takes 4.973 seconds (setting a pointer to zero should be immediate). While the call to the function is still taking (externally) ~20 seconds. This test seems simpler, easier to run: time b5a0sh -c ' TIMEFORMAT="real: %R"; a=$(seq 20000); f2(){ :; }; echo start>&2; time set -- $a; time f2 "$@"; time set --' Which yields: bash b5b2sh ksh 0.097 8.154 0.020 0.107 39.321 0.020 0.003 5.470 0.000 0.239s 52.975s 0.085s
