vmstat Command
The vmstat (virtual memory statistics) command in Linux is used to report information about processes, memory, paging, block IO, traps, and CPU activity. It's a valuable tool for system administrators to monitor system performance and identify bottlenecks.
Syntax
Description
vmstat reports information about processes, memory, paging, block IO, traps, and cpu activity. The first report produced gives statistics since the last reboot. Subsequent reports give statistics collected at a variable time interval.
Common uses include:
- Monitor system performance
- Identify memory bottlenecks
- Analyze CPU utilization
- Track I/O activity
Common Options
| Option | Description |
|---|---|
-a, --active |
Display active/inactive memory |
-f, --forks |
Display number of forks since boot |
-m, --slab |
Display slabinfo |
-s, --stats |
Display a table of various event counters and memory statistics |
-d, --disk |
Report disk statistics |
-p, --partition |
Report disk statistics for a specific partition |
-S unit, --unit unit |
Specify unit of display for memory (k, M, G, T) |
Examples
Display a single report
Displays a single report of virtual memory statistics since the last reboot.
Monitor continuously every 3 seconds
Provides continuous reports every 3 seconds until interrupted (Ctrl+C).
Monitor 5 times every 2 seconds
Provides 5 reports, each 2 seconds apart.
Display active/inactive memory
Shows active and inactive memory in the memory section.
Display disk statistics
Reports statistics for each disk.