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The vmstat command will display statistics about system processes, memory, swap, I/O, and CPU performance. The following command will display extended statistics (-x), the number of times (-t) each report should be displayed for CPU utilization (-c). The following command will break the CPU utilization into user processes, system processes, I/O wait and idle time. To list the individual report use -c, -d and -h switch for CPU utilization, device utilization and network file system utilization. Running the following command without any options displays all three reports. This utility display system’s average CPU utilization since the last reboot. The iostat command list CPU utilization, device utilization and network file system utilization.
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By default, the top command updates data every 5 seconds.
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The top command displays a real-time view of performance-related data of all running processes in a system.
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