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--- docker_rates.sh [2025/11/02 15:04] – created 172.18.0.1
+++ docker_rates.sh [2025/11/02 15:27] (current) – admin
@@ Line 1: / Line 1: @@
 ====== Docker rates.sh ======
 {{tag>docker commands}}
 This prints out a table of instantaneous network bandwidth use.
+===== Python version =====
+<code>
+#!/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()
+</code>
+===== Bash version =====
 <code>
 #!/usr/bin/env bash