vmstat Command: Tutorial & Examples
Display performance statistics
vmstat is a command-line utility that displays information about virtual memory statistics in a computer running Unix or Linux. The information provided by
details about processes, memory usage, paging, block input/output, and CPU activity.
The basic syntax for using
vmstat [options] [delay [count]]
options allow you to specify which statistics you want to see, and the
count parameters allow you to specify how frequently
vmstat should update the display
and for how many times.
vmstat displays a summary of virtual memory statistics, including the following information:
procs: The number of processes in the system, including both running and blocked processes.
r: The number of processes waiting for run time.
b: The number of processes in uninterruptible sleep.
memory: Information about memory usage, including total available memory, used memory, and free memory.
swap: Information about swap space usage, including total swap space, used swap space, and free swap space.
io: Information about block input/output, including the number of blocks read from and written to disk.
system: Information about CPU activity, including the number of interrupts per second and the number of context switches per second.
cpu: Information about CPU utilization, including the percentage of time spent in user mode, system mode, and idle.
Typical output may look like this:
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 13 0 1686016 263224 500408 7675080 0 0 18 128 0 0 54 2 44 1 0
You can use
vmstat to monitor the performance of your system and identify potential bottlenecks or issues with resources such as memory, CPU, or disk I/O. By running
over time and observing changes in the statistics, you can get a better understanding of how your system is being used and identify areas where you might need to make adjustments
CleverUptime uses the raw data from
/proc/vmstat to detect performance problems on your server or VM.