1.mpstat

Report processors related statistics.

2.iostat

Report Central Processing Unit (CPU) statistics and input/out-put statistics for devices, partitions and network filesystems (NFS).

3.free

Display amount of free and used memory in the system

4.netstat

Print network connections, routing tables, interface statis-tics, masquerade connections, and multicast memberships

5.nmon

nmon is designed for performance specialists to use for monitoring and analyzing performance data.

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