Live monitor

The monitor samples the machine’s I/O rates and the processes behind them.

diskgoup monitor sample

network ↓ 0 B/s · ↑ 12.4 KB/s · disk read 1.2 MB/s · write 88.1 KB/s · used 121.4 GB

Watching

diskgoup monitor watch --interval 1 --processes 5

╭───────────────╮
│ Sample 3      │
├───────────────┤
│ Network ↓     │   14.2 KB/s
│ Network ↑     │  102.4 KB/s
│ Disk read     │   1.2 MB/s
│ Disk write    │   88.1 KB/s
│ Disk used     │ 121.4 GB (25%)
╰───────────────╯

Option	Default	What it does
--interval SECONDS	2.0	Seconds between samples.
--count N	0 (forever)	Number of samples to take.
--processes N	0	Show the top N processes by memory.

--count 0 runs until interrupted.

How the rates are measured

The readings are sampled, not counted: the first call establishes a baseline and every later call reports the delta since the previous one. That is what makes a rate rather than a total.

The counters come from psutil:

Metric	Source
Network ↓ / ↑	psutil.net_io_counters() — bytes received / sent
Disk read / write	psutil.disk_io_counters() — bytes read / written
Disk used / total	psutil.disk_usage() for the home directory

On a platform that does not expose the network or disk counters, the sample comes back with zeroes rather than failing.

Processes

diskgoup monitor watch --processes 5

╭────────────────────────────────────────────────────────────╮
│ Processes                                                │
├──────┬─────────────────┬─────────┬──────────┬─────────────┤
│  PID │ Name            │  CPU %  │  Memory  │             │
├──────┼─────────────────┼─────────┼──────────┼─────────────┤
│  412 │ Chrome Helper   │   12.4  │  412 MB  │             │
│ 1204 │ node            │    4.1  │  188 MB  │             │
╰──────┴─────────────────┴─────────┴──────────┴─────────────┯

The processes are sorted by memory, which is the number that explains where a disk analyser usually disagrees with a task manager. Processes that exit or refuse to be inspected are skipped rather than reported as errors.

JSON output

diskgoup --json monitor sample

{
  "timestamp": 1735689600.0,
  "network": { "down": 0.0, "up": 12697.12 },
  "disk": { "read": 1258291.2, "write": 90213.76, "usage": 130346414080.0, "total": 494384795136.0, "used_percent": 26.4 },
  "processes": [
    { "pid": 412, "name": "Chrome Helper", "cpu": 12.4, "memory": 432013312 }
  ]
}