• 1 Introduction
  • 1.1 Overview
• 2 Step by step instructions on RT-Profiling tool
  • 2.1 Setup environment
    • 2.1.1 Install software dependencies
    • 2.1.2 Get the source code
    • 2.1.3 Build latency utilities
    • 2.1.4 Build cyclictest utilities
    • 2.1.5 Make nmon/nmonchart executable
  • 2.2 Generate RT performance data
    • 2.2.1 Generate Jitter/Cycle data with latency
    • 2.2.2 Generate Jitter/Cycle data with cyclictest
  • 2.3 Collect RT performance data
    • 2.3.1 Observe the performance data in interactive mode
    • 2.3.2 Capture the performance data in data collector mode
  • 2.4 Generate html page
  • 2.5 Analyze the result
  • 2.6 Use node.js to directly generate html page recognized by eCharts from .nmon file
    • 2.6.1 Dependency software
    • 2.6.2 Generate html page
  • 2.7 Display html page based on eCharts
    • 2.7.1 Page button function
    • 2.7.2 Scatter chart page function
    • 2.7.3 Bar chart page function
    • 2.7.4 Line chart page function
• 3 Roadmap
  • 3.1 Supported features
  • 3.2 In progress features
  • 3.3 Todo Features
• 4 License

In industrial controller scenarios, the real-time performance indicators like jitter & cycle time are the two key criteria to evaluate the performance of RT control system. However, how to troubleshoot and tune real-time performance is always a challenge to developers. There are many factors like IRQs, network traffic could affecting the overall performance of RT control system.

This document provides a step-by-step guidance for RT control system developers/analyzers on how to setup, collect and analyze real-time control related jitter/cycle parameters as well as other system characters of the real-time control system like CPU utilization, disks accessing, network transferring, IRQs using customized nmon/nmonchart toolset.

The RT profiling tool should be able to run on all the latest Linux distributions theoretically. We will use Linux Ubuntu 16.04 x64 LTS as the default environment throughout this guide in order to minimize clutters caused by various Linux distributions.

Please install gcc, make, git utilities and ncurses dev lib on the target system if any of these packages is unavailable on the system.

1. Connect to the internet.

2. Open a command prompt terminal window.

3. Type following instruction in the terminal, input root password as prompt. Please adjust the command accordingly to install the corresponding dependency if you use Fedora or other Linux distributions.

sudo apt install gcc libncurses5-dev make git build-essential kernel-package fakeroot libssl-dev

Get the latest source code of RT-Profiling tool from the git server or from package file offline.

1. Get the source code from the git server.

git clone https://github.com/intel/rt-perf-profiling-tool

Type following commands in the terminal to build latency utilities.

1. Get xenomai source code.

wget https://xenomai.org/downloads/xenomai/stable/xenomai-3.0.7.tar.bz2
tar -jxvf xenomai-3.0.7.tar.bz2

2. Apply the patch for latency utility. Where xxx stands for the absolute path of patch 0001-capture-jitter-performance-in-share-memory.patch under collection/latency folder you got at step 2.1.2.

cd xenomai-3.0.7/
git apply --reject xxx

3. Build latency utility.

./configure --with-core=cobalt --enable-smp --enable-pshared
make

Type following commands in the terminal to build cyclictest utilities.

1. Get rt-tests source code v1.0.

git clone https://git.kernel.org/pub/scm/utils/rt-tests/rt-tests.git
cd rt-tests/
git checkout stable/v1.0

2. Apply the patch for cyclictest utility. Where yyy stands for the absolute path of patch 0001-capture-latency-in-share-memory.patch under collection/cyclictest folder you got at step 2.1.2.

git apply --reject yyy

6. Build cyclictest utility.

make

Build nmon utility, and then make nmon utility and nmonchart script executable at any place.

1. Move to the nmon directory.

cd rt_profiling-tool/agent/nmon

2. Execute following command to build nmon binary. Where arch stands for the CPU architecture of the system under test, os stands for the target operating system nmon will be executed. We'll use nmon_AMD64_ubuntu1604 as an example here. Please specify the designated configuration combination value as the parameter of the make according to the real condition.

make <nmon_arch_os>

3. Setup the symbolic link of nmon utility. Here we use nmon_AMD64_ubuntu1604 as the sample, please adjust it for your self.

sudo ln -s rt_profiling-tool/agent/nmon/nmon_AMD64_ubuntu1604 /usr/local/bin/nmon

4. Setup the symbolic link of nmonchart script.

sudo ln -s rt_profiling-tool/analysis/nmonchart/nmonchart /usr/local/bin/nmonchart

We can use latency or cyclictest utility to generate RT performance data.

You can launch latency in terminal to generate RT performance data.

sudo ./latency -r

-r: update jitter performance in share memory

Notes: If you met following error message:

0"000.000| BUG in low_init(): [main] Cobalt core not enabled in kernel

It means that the cobalt core of xenomai is not enabled in the linux kernel. Please build the xenomai enabled kernel and utilize it as the system kernel.

You can launch cyclictest in terminal to generate RT performance data.

sudo ./cyclictest -N -t 4 -e

-N: show results in nanoseconds

-t 4: start 4 threads to measure latency

-e: update latency performance in share memory

Nmon can gives you a huge amount of important performance information in one go. It can output the data on the screen in interactive mode or save the data to a comma separated file for analysis in data collector mode.

You can observe the Jitter time, Cycle time as well as CPU, memory, network, disks etc. data directly on the screen and updated every second if you launch the nmon without arguments.

1. Open a terminal, type nmon. Nmon with help info page will pop up.

2. You can press the corresponding keys to toggle on or off statistics. Say, you can press "ecCUd" to show RT info, CPU Utilization, CPU Utilization Stats, CPU Utilization Wide View and Disk I/O info.

3. You can press "+" or "-" key to increase or decrease nmon sampling intervals in real time. By default, the screen refresh time is two seconds. The minimum refresh time is one second.

1. Open a terminal, launch nmon utility with parameters specified. The .nmon data files it captured will be saved under YYMMDD_HHMM folder(where YYMMDD and HHMM are the beginning time of the collection).

nmon -feiTU -s 1 -c 36000

Notes: Following parameters are supported when nmon is launched.

-f: Must be the first option on the line (switches off interactive mode). Saves data to a CSV Spreadsheet format .nmon file in the local directory

-e: Specify RT Performance info to be collected

-i: Specify IRQ info to be collected.

-t: Collect Top Process info also

-T: Collect command line info also

-U: Collect CPU Utils info als；

-s : Time between data snapshots

-c : Of snapshots before exiting。

Eg: -feiTU -s 1 -c 36000 stands for collect the data for 36000 times with time interval for one second. IRQ and Top process info are collected also. The .nmon file will be saved on current folder for further investigation by default.

Open a terminal, move to the folder where nmon utilities are saved. Execute nmonchart script to generate html files.

nmonchart HHMMDD__HHMMM

HHMMDD_HHMMM is the folder name where .nmon data files are stored.

The webpage files xxxx.html will be generated under HHMMDD_HHMMM folder.

Double click the xxxx.html file generated by nmonchart to open the dynamic webpage as Figure 2.5.1.

Figure 2.5.1 Homepage of nmonchart

You can click Configuration, Top Summary, Top Command and Top Disk buttons separately on the first row to get the overall information, overall CPU consumptions and disk usage.

You can click on CPU util. CPU Use and CPU All Utils, button to monitor CPU related criteria.

Figure 2.5.2 nmonchart

If node.js is not installed on the system, download and install node.js first.

Open the CMD window, enter the directory where nmontohtml.js is located, and execute the command. XXX is the full or relative path of the .nmon file or folder to be converted, separated by spaces between multiple files

node nmonToHtml.js XXX XXX

Notes：The HTML generated by nmontohtml.js file depends on the files in JS folder and CSS folder, so please do not change the file structure to avoid HTML file display and function errors. The main dependency file for the chart is eCharts.min.js. Including Chart, Coordinate Systems and Components Chart: Including Bar, Line, Pie, Scatter and EffectScatter.

Figure 2.6.1 Chart

Coordinate Systems: Including Grid.

Figure 2.6.2 Coordinate Systems

Components: Inculding Title, Legend, Tooltip, MarkPoint, MarkLine, MarkArea, Timeline and DataZoom.

Figure 2.6.3 Components

Check "Code Compression" to indicate that the customized file is compressed: "echart.min.js".

Figure 2.6.4 Compress

The main dependency file for the HTML is jquery-3.4.1.min.js. Version 3.4.1 is recommended. Download address: https://jquery.com/download/. Click "Download the compressed, production jQuery 3.4.1" on the page to perform the download.

Figure 2.6.5 JQuery Download

When the .nmon file is too large, it takes a long time to generate the HTML file. Please wait patiently.

After hovering and selecting, the color will be changed and shadow background will be added for easy recognition, as Figure 2.7.1.

Figure 2.7.1 page button function

1. When the mouse hovers over the circle, the detailed data of the current circle will be displayed on the edge of the mouse and inside the circle, as Figure 2.7.2.

Figure 2.7.2 Scatter chart function 1

2. When the mouse hovers over the legend on the right, the detailed data of the corresponding circle will be displayed in the circle corresponding to the legend, as Figure 2.7.3.

Figure 2.7.3 Scatter chart function 2

3. When the mouse clicks on the legend, the data corresponding to the currently clicked legend will be hidden. Click again to restore, as Figure 2.7.4.

Figure 2.7.4 Scatter chart function 3

The display mode of the page is stacked display.

1. When the mouse hovers over the histogram, the data of the corresponding legend in the area will be displayed, as Figure 2.7.5.

Figure 2.7.5 Bar chart function 1

2. When the mouse clicks on the legend, the data corresponding to the currently clicked legend will be hidden. Click again to restore, as Figure 2.7.6.

Figure 2.7.6 Bar chart function 2

1. The X axis is displayed as a dynamic area, which can be zoomed freely. Use through the mouse wheel or the area thumbnail below (click somewhere of the area thumbnail or stretch the covered area), as Figure 2.7.7.

Figure 2.7.7 Line chart function 1

2. When the mouse hovers over the legend, the line chart node of the corresponding legend will be marked, as Figure 2.7.8.

Figure 2.7.8 Line chart function 2

3. When you click the legend, the corresponding line chart will be displayed on the right Y axis, as Figure 2.7.9.

Figure 2.7.9 Line chart function 3

4. When the mouse hovers over the chart, the data of all the lines chart on the X axis corresponding to the mouse position will be displayed, as Figure 2.7.10.

Figure 2.7.10 Line chart function 4

• Nmon based data agent
  • Support cyclic data source
  • Support latency data source
  • Support real-time data metrics
  • Support disk/mem/net/interrupt etc.. Data metrics
• Web based visualization
  • Charting for misc. data metrics
  • Real-time data metrics showing with defined & selected other metrics
• Web based visualization (eCharts page)
  • Change code base to echarts based chart
  • Dual-Y axis to show data in different granularity
  • Flexible chart area display
  • Button selection for more intuitive display

• Web based visualization (eCharts page)
  • eCharts page style optimization

• Nmon based data agent
  • support msi_latency data source
• Web based visualization
  • Charting for misc. data metrics
  • Real-time data metrics showing with defined & selected other metrics
  • jitter statistics analysis
  • Scoring
  • normal distribution
  • Sorting
  • Plugin based value-adding analysis module framework & sample code
  • Correlation
  • Abnormal
  • Value added modules

The source code is licensed under GNU General Public License v3.0 or later. See LICENSE file for details. It includes software developed from 3rd-party, See NOTICE file for details.