The vmstat command provides information in following categories :-
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st Here procs stands for processes, memory for memory usage, swap for the pages pulled in and pulled out of swap, io for disk usage, system for the number of times the kernel switches into kernel code and cpu for time used by different parts of the system. By interpreting its output we can check how our system is performing and by changing some factors we can improve system performance.