Why the external dos command/program is so slow in 64 bit window?
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I try executing some external commands/programs in Matlab (R2010a, 64bit) but they are very slow. Here is an example: Matlab program: disp('Test external command in Matlab');
for i = 1:5 tic system('cd .'); toc end
Results: Test external command in Matlab Elapsed time is 7.136996 seconds. Elapsed time is 6.094630 seconds. Elapsed time is 5.574957 seconds. Elapsed time is 6.235473 seconds. Elapsed time is 5.973438 seconds.
My computer is Dell Optiplex 980, Windows 7. I have not met the same problem in Linux or 32bit Matlab.
the cyclist on 22 Feb 2011
I am using R2010b on a 64-bit Mac, and I do not see that behavior. My elapsed times are on the order of milliseconds.
Xiangrui Li on 3 May 2017
I observed the slowness for both win32 and win64. I just posted a question why redirecting the output to a file improve the performance. It is strange that, even if there is no output, redirecting still makes it faster.
tic, for i = 1:5, system('cd .'); end; toc
Elapsed time is 0.627796 seconds.
tic, for i = 1:5, system('cd . >myFile'); end; toc
Elapsed time is 0.111956 seconds.