vmstat Plugin
Report virtual memory, processes, CPU, I/O, and system statistics.
Quickstart
# One-shot system statistics
vmstat
# Continuous monitoring (every 2 seconds, 5 times)
vmstat 2 5
# Show active/inactive memory
vmstat -a
# Disk statistics
vmstat -d
# Disk summary
vmstat -D
# Partition read/write stats
vmstat -p sda1
# Slab allocator statistics
vmstat -s
# Show version
vmstat --version
Common Flags
| Flag | Description |
|---|---|
-a |
Show active/inactive memory |
-d |
Disk statistics (read/write per disk) |
-D |
Disk summary statistics |
-p |
Partition-specific statistics |
-s |
Slab allocator statistics |
-t |
Timestamp on each line |
-S |
Unit (k/K/m/M) |
-w |
Wide output |
Fields Explained
| Field | Description |
|---|---|
| r | Processes waiting for CPU |
| b | Processes in uninterruptible sleep |
| swpd | Used swap memory |
| free | Free memory |
| buff | Buffer cache |
| cache | Page cache |
| si/so | Swap in/out |
| bi/bo | Block in/out |
| us/sy/id/wa | CPU time percentages |
Tips
- First line of output shows averages since boot; subsequent lines show delta
- Use
delayandcountfor real-time monitoring - High
wa(wait) indicates I/O bottleneck - High
si/soindicates swapping pressure (needs more RAM)