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Which command will be faster? y?


 
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Top Forums UNIX for Dummies Questions & Answers Which command will be faster? y?
# 1  
Old 07-30-2009
Which command will be faster? y?

i)wc -c/etc/passwd|awk'{print $1}'

ii)ls -al/etc/passwd|awk'{print $5}'
# 2  
Old 07-30-2009
it depends on your file size...
# 3  
Old 07-30-2009
Don't know your platform but you may have the 'time' command available. It will give you the time it takes for a command to finish. That way you can test it yourself. On a management server we have:

Code:
$ time wc -c /etc/passwd | awk '{print $1}'
1958

real    0m0.003s
user    0m0.000s
sys     0m0.005s

$ time ls -al /etc/passwd | awk '{print $5}'
1958

real    0m0.006s
user    0m0.002s
sys     0m0.005s

# 4  
Old 07-30-2009
How about:

wc -c < /etc/passwd which will increase performance more than either by avoiding awk entirely.

Or even stat -c '%s' /etc/passwd which only checks the file size instead of actually reading the entire thing.

Last edited by Corona688; 07-30-2009 at 07:11 PM..
# 5  
Old 07-30-2009
Code:
$ time wc -c /etc/passwd | awk '{print $1}'
1958

real    0m0.004s
user    0m0.001s
sys     0m0.003s

$ time ls -al /etc/passwd | awk '{print $5}'
1958

real    0m0.007s
user    0m0.000s
sys     0m0.006s

$ time wc -c < /etc/passwd
1958

real    0m0.002s
user    0m0.001s
sys     0m0.001s

$ time stat -c '%s' /etc/passwd
1958

real    0m0.002s
user    0m0.001s
sys     0m0.001s

And the winner is......option #3. #3 & #4 tied for speed but I had to give it to #3 for being easier to type Smilie
 

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