The dpdk-telemetry.py script is useful for getting telemetry interactively, but sometimes we want to monitor stats over time, so add a telemetry-watcher script to do so.
Start off such a script with basic arg processing, and connecting to dpdk-telemetry as a subprocess, so that we can send-receive commands from it. Signed-off-by: Bruce Richardson <[email protected]> Acked-by: Stephen Hemminger <[email protected]> --- doc/guides/tools/index.rst | 1 + doc/guides/tools/telemetrywatcher.rst | 56 ++++++++ usertools/dpdk-telemetry-watcher.py | 200 ++++++++++++++++++++++++++ usertools/meson.build | 1 + 4 files changed, 258 insertions(+) create mode 100644 doc/guides/tools/telemetrywatcher.rst create mode 100755 usertools/dpdk-telemetry-watcher.py diff --git a/doc/guides/tools/index.rst b/doc/guides/tools/index.rst index 8ec429ec53..13f75a5bc6 100644 --- a/doc/guides/tools/index.rst +++ b/doc/guides/tools/index.rst @@ -14,6 +14,7 @@ DPDK Tools User Guides pmdinfo dumpcap pdump + telemetrywatcher dmaperf flow-perf securityperf diff --git a/doc/guides/tools/telemetrywatcher.rst b/doc/guides/tools/telemetrywatcher.rst new file mode 100644 index 0000000000..e813bf0207 --- /dev/null +++ b/doc/guides/tools/telemetrywatcher.rst @@ -0,0 +1,56 @@ +.. SPDX-License-Identifier: BSD-3-Clause + Copyright(c) 2026 Intel Corporation + +dpdk-telemetry-watcher Application +=================================== + +The ``dpdk-telemetry-watcher`` tool is a Data Plane Development Kit (DPDK) utility +that provides continuous monitoring of DPDK telemetry statistics on the command line. +It wraps the ``dpdk-telemetry.py`` script to provide real-time statistics display capabilities. + + +Running the Application +----------------------- + +The tool has a number of command line options: + +.. code-block:: console + + dpdk-telemetry-watcher.py [options] stat1 stat2 ... + + +Options +------- + +.. program:: dpdk-telemetry-watcher.py + +.. option:: -h, --help + + Display usage information and quit + +.. option:: -f FILE_PREFIX, --file-prefix FILE_PREFIX + + Provide file-prefix for DPDK runtime directory. + Passed to ``dpdk-telemetry.py`` to identify the target DPDK application. + Default is ``rte``. + +.. option:: -i INSTANCE, --instance INSTANCE + + Provide instance number for DPDK application when multiple applications are running with the same file-prefix. + Passed to ``dpdk-telemetry.py`` to identify the target DPDK application instance. + Default is ``0``. + +.. option:: -l, --list + + List all possible file-prefixes and exit. + This is useful to discover which DPDK applications are currently running. + +Dependencies +------------ + +The tool requires: + +* Python 3 +* The ``dpdk-telemetry.py`` script must be available in the same directory + or in the system PATH +* A running DPDK application with telemetry enabled diff --git a/usertools/dpdk-telemetry-watcher.py b/usertools/dpdk-telemetry-watcher.py new file mode 100755 index 0000000000..a5ac293d06 --- /dev/null +++ b/usertools/dpdk-telemetry-watcher.py @@ -0,0 +1,200 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: BSD-3-Clause +# Copyright(c) 2025 Intel Corporation + +""" +Script to monitor DPDK telemetry statistics on the command line. +Wraps dpdk-telemetry.py to provide continuous monitoring capabilities. +""" + +import argparse +import subprocess +import sys +import os +import shutil +import errno +import json + + +def get_app_name(pid): + """return the app name for a given PID, for printing""" + proc_cmdline = os.path.join("/proc", str(pid), "cmdline") + try: + with open(proc_cmdline) as f: + argv0 = f.read(1024).split("\0")[0] + return os.path.basename(argv0) + except IOError as e: + # ignore file not found errors + if e.errno != errno.ENOENT: + raise + return None + + +def find_telemetry_script(): + """Find the dpdk-telemetry.py script in the script directory or PATH. + + Returns: + str: Path to the dpdk-telemetry.py script + + Exits: + If the script cannot be found + """ + # First, try to find it in the same directory as this script + script_dir = os.path.dirname(os.path.abspath(__file__)) + telemetry_script = os.path.join(script_dir, "dpdk-telemetry.py") + + # If not found locally, check if it's in PATH + if not os.path.exists(telemetry_script): + telemetry_in_path = shutil.which("dpdk-telemetry.py") + if telemetry_in_path: + telemetry_script = telemetry_in_path + else: + print( + "Error: dpdk-telemetry.py not found in script directory or PATH", + file=sys.stderr, + ) + sys.exit(1) + + return telemetry_script + + +def create_telemetry_process(telemetry_script, args_list): + """Create a subprocess for dpdk-telemetry.py with pipes. + + Args: + telemetry_script: Path to the dpdk-telemetry.py script + args_list: List of arguments to pass to the script + + Returns: + subprocess.Popen: Process handle with stdin/stdout/stderr pipes + + Exits: + If the process cannot be created + """ + # Build the command + cmd = [sys.executable, telemetry_script] + args_list + + try: + process = subprocess.Popen( + cmd, + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE, + text=True, + bufsize=1, # Line buffered + ) + return process + except FileNotFoundError: + print("Error: Python interpreter or script not found", file=sys.stderr) + sys.exit(1) + except Exception as e: + print(f"Error running dpdk-telemetry.py: {e}", file=sys.stderr) + sys.exit(1) + + +def query_telemetry(process, command): + """Send a telemetry command and return the parsed JSON response. + + Args: + process: The subprocess.Popen handle to the telemetry process + command: The telemetry command to send (e.g., "/info" or "/ethdev/stats,0") + + Returns: + dict: The parsed JSON response with the command wrapper stripped, + or None if there was an error + """ + # Send the command + process.stdin.write(f"{command}\n") + process.stdin.flush() + + # Read the JSON response + response = process.stdout.readline() + try: + data = json.loads(response) + # When run non-interactively, the response is wrapped with the command + # e.g., {"/info": {"version": ..., "pid": ...}} + # or {"/ethdev/stats,0": {...}} + # The response should have exactly one key which is the command + if len(data) == 1: + # Extract the value, ignoring the key + return next(iter(data.values())) + else: + return data + except (json.JSONDecodeError, KeyError): + return None + + +def print_connected_app(process): + """Query and print the name of the connected DPDK application. + + Args: + process: The subprocess.Popen handle to the telemetry process + """ + info = query_telemetry(process, "/info") + if info and "pid" in info: + app_name = get_app_name(info["pid"]) + if app_name: + print(f'Connected to application: "{app_name}"') + + +def main(): + """Main function to parse arguments and run dpdk-telemetry.py with a pipe""" + + # Parse command line arguments - matching dpdk-telemetry.py parameters + parser = argparse.ArgumentParser( + description="Monitor DPDK telemetry statistics on the command line" + ) + parser.add_argument( + "-f", + "--file-prefix", + default="rte", + help="Provide file-prefix for DPDK runtime directory", + ) + parser.add_argument( + "-i", + "--instance", + default=0, + type=int, + help="Provide instance number for DPDK application", + ) + parser.add_argument( + "-l", + "--list", + action="store_true", + default=False, + help="List all possible file-prefixes and exit", + ) + + args = parser.parse_args() + + # Find the dpdk-telemetry.py script + telemetry_script = find_telemetry_script() + + # Build arguments list + args_list = ["-f", args.file_prefix, "-i", str(args.instance)] + + if args.list: + args_list.append("-l") + # For --list, just run the command directly without pipes + cmd = [sys.executable, telemetry_script] + args_list + return subprocess.run(cmd).returncode + + # Run dpdk-telemetry.py with pipes for stdin and stdout + process = create_telemetry_process(telemetry_script, args_list) + + # Get and display the connected application name + print_connected_app(process) + + # TODO: Add monitoring logic here + + # Clean up + process.stdin.close() + process.stdout.close() + process.stderr.close() + process.wait() + + return 0 + + +if __name__ == "__main__": + sys.exit(main()) diff --git a/usertools/meson.build b/usertools/meson.build index eb48e2f440..114d0a65b4 100644 --- a/usertools/meson.build +++ b/usertools/meson.build @@ -12,6 +12,7 @@ install_data([ 'dpdk-hugepages.py', 'dpdk-rss-flows.py', 'dpdk-telemetry-exporter.py', + 'dpdk-telemetry-watcher.py', ], install_dir: 'bin') -- 2.51.0
