Mastering dstat: Real‑Time Linux System Monitoring Made Easy

dstat is a versatile system‑information tool that replaces utilities such as vmstat, iostat, netstat, nfsstat, and ifstat, offering colored, real‑time output that refreshes every second.

Installation

Two common methods:

Using the package manager: yum install -y dstat Downloading the RPM from the official site and installing it:

wget http://dag.wieers.com/rpm/packages/dstat/dstat-0.6.7-1.rh7.rf.noarch.rpm && rpm -ivh dstat-0.6.7-1.rh7.rf.noarch.rpm

Basic Usage

After installation, run dstat. The default option set -cdngy displays CPU, disk, network, paging, and system information, updating every second. You can specify an interval and count, e.g., dstat 5 for a 5‑second interval or dstat 5 10 for 10 reports at that interval.

Example Output

[root@iZ23uulau1tZ ~]# dstat
----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read writ| recv send| in out | int csw
0 0 99 0 0 0|7706B 164k| 0 0 | 0 0 | 189 225
0 0 100 0 0 0| 0 0 |4436B 826B| 0 0 | 195 248
...

Key fields: cpu hiq and siq represent hardware and software interrupt counts; system int and csw are interrupt and context‑switch counts.

Syntax

General form:

dstat [-afv] [options...] [delay [count]]

Common Options

-c

: CPU usage (user, system, idle, wait, hardware and software interrupts). -C: Select specific CPUs, e.g., -C 0,1. -d: Disk read/write statistics. -D hda,total: Include specific disks. -n: Network statistics. -N eth1,total: Choose network interfaces. -l: System load average. -m: Memory usage. -g: Page usage. -p: Process statistics. -s: Swap usage. -r: I/O request statistics. -y: General system status. --ipc: IPC queues and signals. --socket: TCP/UDP socket status. -a: Alias for -cdngy (default set). -v: Verbose mode, equivalent to -pmgdsc -D total. --output FILE: Write results in CSV format to FILE, e.g., dstat --output /root/dstat.csv &.

Advanced Usage Example

Monitor swap, processes, sockets, and filesystem with timestamps: dstat -tsp --socket --fs Sample output shows date/time, swap used/free, process counts, socket statistics, and filesystem usage.

To save the monitoring data to a CSV file: dstat -tsp --socket --fs --output /tmp/ds.csv The generated CSV can be opened in Excel for charting.

Use dstat --list to display all built‑in parameters and available plugins. Built‑in parameters are listed under “internal”, while plugins reside in /usr/share/dstat and extend functionality (e.g., battery, MySQL, etc.), though some plugins require additional packages.