[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Unexpected delay in using arguments.
From: |
Chet Ramey |
Subject: |
Re: Unexpected delay in using arguments. |
Date: |
Wed, 30 Jan 2019 14:20:49 -0500 |
User-agent: |
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 |
On 1/1/19 9:57 PM, Bize Ma wrote:
> Chet Ramey (<chet.ramey@case.edu <mailto:chet.ramey@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.
In the development distributions, always available at
http://git.savannah.gnu.org/cgit/bash.git/snapshot/bash-devel.tar.gz
Or you could just clone the git tree.
>
> 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):
I'm going to assume you're running the pre-release distributions on a
Linux system where the debugging code in the bash malloc is enabled.
When I try timing the entire script on bash-5.0.2 (Mac OS X), adding `time'
calls before `f2 "$@"' and `main', I get
args = 1
1 function no args yes real: 0.006
2 function yes args yes real: 0.012
3 function yes args no real: 0.012
args = 20000
1 function no args yes real: 0.006
2 function yes args yes real: 0.012
3 function yes args no real: 0.013
real: 0.078
real: 0.503
real 0m0.529s
user 0m0.464s
sys 0m0.104s
which is comparable to ksh93, which produces
real 0m0.459s
user 0m0.349s
sys 0m0.107s
for the entire script.
So I'm comfortable saying there's no big performance issue here.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/