VMSTAT

vmstat stands for virtual memory statistics;

It collects and displays summary information about

memory,

processes,

 interrupts,

 paging and

 block I/O information.

By specifying the interval, it can be used to observe system activity interactively.
Most commonly people will use 2 numeric arguments in vmstat;
first is delay or sleep between updates and
the second is how many updates you want to see before vmstat quits.
Please note this is not the full syntax of vmstat and also it can vary between OSs. Please refer your OS man page for more information.
To run vmstat with 7 updates, 10 seconds apart type
#vmstat 10 7