This prints out a table of instantaneous network bandwidth use.
#!/usr/bin/env python3
"""
rates.py — instantaneous per-container network rates (B/s / Mbps)
Python 3.11.9 — no external packages required.
Usage examples:
./rates.py # default 1s interval, show all containers
./rates.py 2 --top 10 # 2s interval, show top 10
"""
from __future__ import annotations
import subprocess, time, sys, shutil, signal, os
from datetime import datetime
from typing import Dict, Tuple
INTERVAL = float(sys.argv[1]) if len(sys.argv) > 1 and sys.argv[1].replace('.','',1).isdigit() else 1.0
TOP = None
# simple argument parsing for --top N
if "--top" in sys.argv:
try:
TOP = int(sys.argv[sys.argv.index("--top") + 1])
except Exception:
TOP = None
NAME_WIDTH = 30
def run(cmd: list[str]) -> str:
res = subprocess.run(cmd, capture_output=True, text=True)
return res.stdout.strip()
def list_container_ids() -> list[str]:
out = run(["docker", "ps", "-q"])
if not out:
# fallback to podman if docker missing
out = run(["podman", "ps", "-q"])
return [x for x in out.splitlines() if x.strip()]
def inspect_container(id_: str) -> Tuple[str, int]:
"""Return (name, pid). name without leading slash."""
out = run(["docker", "inspect", "--format", "{{.Name}}\t{{.State.Pid}}", id_])
if not out:
out = run(["podman", "inspect", "--format", "{{.Name}}\t{{.State.Pid}}", id_])
if not out:
return (id_, 0)
parts = out.split("\t")
name = parts[0].lstrip("/") if parts else id_
pid = int(parts[1]) if len(parts) > 1 and parts[1].isdigit() else 0
return name, pid
def read_net_dev_total(pid: int) -> Tuple[int,int]:
"""Return (rx_total, tx_total) bytes summed across interfaces for a PID's net namespace."""
path = f"/proc/{pid}/net/dev"
try:
with open(path, "r") as f:
lines = f.readlines()[2:]
except Exception:
return 0, 0
rx = 0
tx = 0
for line in lines:
cols = line.split()
# linux /proc/net/dev fields: iface: rx_bytes ... tx_bytes ...
# after split, rx_bytes is at index 1, tx_bytes at index 9 (0-based)
if len(cols) >= 10:
try:
rx += int(cols[1])
tx += int(cols[9])
except ValueError:
continue
return rx, tx
def human_bytes(v: int) -> str:
if v >= (1<<30):
return f"{v/(1<<30):.2f} GB"
if v >= (1<<20):
return f"{v/(1<<20):.2f} MB"
if v >= (1<<10):
return f"{v/(1<<10):.2f} KB"
return f"{v} B"
def mbps(v: int) -> float:
return v / 125000.0
def truncate(s: str, w: int) -> str:
return (s if len(s) <= w else s[:w-3] + "...")
def clear_screen():
print("\x1b[2J\x1b[H", end="")
def gather_snapshot() -> Dict[str, Tuple[str,int,int,int]]:
"""
return dict: id -> (name, pid, rx_total, tx_total)
"""
ids = list_container_ids()
snap = {}
for cid in ids:
name, pid = inspect_container(cid)
rx, tx = (0,0)
if pid > 0 and os.path.exists(f"/proc/{pid}/net/dev"):
rx, tx = read_net_dev_total(pid)
snap[cid] = (name, pid, rx, tx)
return snap
def main():
prev = gather_snapshot()
# honour terminal width for name column
cols = shutil.get_terminal_size((120, 20)).columns
global NAME_WIDTH
NAME_WIDTH = min(NAME_WIDTH, max(12, cols - 70))
try:
while True:
time.sleep(INTERVAL)
now = gather_snapshot()
rows = []
ts = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
for cid, (name, pid, rx_now, tx_now) in now.items():
_, _, rx_prev, tx_prev = prev.get(cid, ("",0,0,0))
# if container restarted, prev might be absent -> diffs are rx_now-0 which is fine but might be large;
# handle negative or weird results
drx = rx_now - rx_prev
dtx = tx_now - tx_prev
if drx < 0: drx = 0
if dtx < 0: dtx = 0
# convert to per-second (interval may not be exactly constant)
rx_rate = int(drx / INTERVAL)
tx_rate = int(dtx / INTERVAL)
total = rx_rate + tx_rate
rows.append({"name": name, "rx": rx_rate, "tx": tx_rate, "tot": total})
# sort descending by total
rows.sort(key=lambda r: r["tot"], reverse=True)
if TOP:
rows = rows[:TOP]
clear_screen()
header = f"{ts} (interval {INTERVAL}s) containers: {len(rows)}"
print(header)
name_w = NAME_WIDTH
hdr = f"{'NAME':{name_w}} {'RX':>12} {'TX':>12} {'TOT':>12} {'RX(Mbps)':>9} {'TX(Mbps)':>9} {'TOT(Mbps)':>9}"
print(hdr)
print("-" * len(hdr))
for r in rows:
n = truncate(r["name"], name_w)
rx_h = human_bytes(r["rx"])
tx_h = human_bytes(r["tx"])
tot_h = human_bytes(r["tot"])
rx_m = f"{mbps(r['rx']):6.2f}"
tx_m = f"{mbps(r['tx']):6.2f}"
tot_m = f"{mbps(r['tot']):6.2f}"
print(f"{n:{name_w}} {rx_h:>12} {tx_h:>12} {tot_h:>12} {rx_m:>9} {tx_m:>9} {tot_m:>9}")
sys.stdout.flush()
prev = now
except KeyboardInterrupt:
print("\nexiting.")
return
if __name__ == "__main__":
main()
#!/usr/bin/env bash
# Instantaneous per-container network rates (B/s). No extra packages.
INTERVAL=1
TMPDIR=${TMPDIR:-/tmp}
PREV="$TMPDIR/net.prev.$$.txt"
NOW="$TMPDIR/net.now.$$.txt"
OUT="$TMPDIR/net.out.$$.txt"
cleanup(){ rm -f "$PREV" "$NOW" "$OUT"; exit 0; }
trap cleanup INT TERM
collect() {
target="$1"
: > "$target"
docker ps -q | while read -r id; do
[ -z "$id" ] && continue
name=$(docker inspect --format '{{.Name}}' "$id" 2>/dev/null | sed 's#/##')
pid=$(docker inspect --format '{{.State.Pid}}' "$id" 2>/dev/null)
if [ -r "/proc/$pid/net/dev" ]; then
read rx tx < <(awk 'NR>2{rx+=$2;tx+=$10}END{print rx,tx}' /proc/"$pid"/net/dev 2>/dev/null || echo "0 0")
else
rx=0; tx=0
fi
# id<TAB>name<TAB>pid<TAB>rx<TAB>tx
printf '%s\t%s\t%s\t%s\t%s\n' "$id" "$name" "$pid" "$rx" "$tx" >> "$target"
done
}
# seed previous snapshot
collect "$PREV"
sleep "$INTERVAL"
while true; do
ts=$(date +"%F %T")
collect "$NOW"
# load previous counters into associative arrays
declare -A PRX PTX PNAME
while IFS=$'\t' read -r id name pid rx tx; do
PRX["$id"]=$rx
PTX["$id"]=$tx
PNAME["$id"]=$name
done < "$PREV"
: > "$OUT"
while IFS=$'\t' read -r id name pid arx atx; do
brx=${PRX[$id]:-0}
btx=${PTX[$id]:-0}
rx_rate=$((arx - brx))
tx_rate=$((atx - btx))
[ "$rx_rate" -lt 0 ] && rx_rate=0
[ "$tx_rate" -lt 0 ] && tx_rate=0
total=$((rx_rate + tx_rate))
# total<TAB>name<TAB>rx_rate<TAB>tx_rate<TAB>total
printf '%d\t%s\t%d\t%d\t%d\n' "$total" "$name" "$rx_rate" "$tx_rate" "$total" >> "$OUT"
done < "$NOW"
echo "==== $ts (rates over ${INTERVAL}s) ===="
if [ -s "$OUT" ]; then
sort -t $'\t' -nr -k1,1 "$OUT" | awk -F'\t' '{printf "%-28s RX:%8d B/s TX:%8d B/s TOT:%8d B/s\n", $2, $3, $4, $5}'
else
echo "No containers found."
fi
mv "$NOW" "$PREV"
sleep "$INTERVAL"
done