Why is sys+user > real in "time command"?

benchmarking, linux, pthreads, time, unix

Solution

It is greater, because it adds the time from all the cores together.

Problem

I have a program that uses pthread library to do the matrix multiplication of 500x500 matrix. Each thread calculates 50 rows of the matrix. When I time its execution: ``` shadyabhi@shadyabhi-desktop:~$ time ./a.out real 0m0.383s user 0m0.810s sys 0m0.000s shadyabhi@shadyabhi-desktop:~$ ``` Why is sys+user is greater than real time?

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