Linux Shell Scripting Cookbook - Third Edition

How it works...

The time command reports these times by default:

• Real: This is the wall clock time-the time from start to finish of the command. This is the elapsed time including time slices used by other processes and the time the process spends when blocked (for example, time spent waiting for I/O to complete).
• User: This is the amount of CPU time spent in user-mode code (outside the kernel) within the process. This is the CPU time used to execute the process. Other processes, and the time these processes spend when blocked do not count toward this figure.
• Sys: This is the amount of CPU time spent in the kernel within the process; the CPU time spent in system calls within the kernel, as opposed to the library code, which runs in the user ...