Why does CPU processing time matter when compared to real wall clock time?

Posted by PeanutsMonkey on Super User See other posts from Super User or by PeanutsMonkey
Published on 2012-08-28T08:28:02Z Indexed on 2012/08/28 9:41 UTC
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linux

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time

I am running the command time 7zr a -mx=9 sample.7z sample.log to gauge how long it takes to compress a file larger than 1GB. The results I get are as follows.

real    10m40.156s
user    17m38.862s
sys     0m5.944s

I have a basic understanding of the difference but don't understand how this plays a role in the time in takes to compress the file. For example should I be looking at real or user + sys?

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