Skip to main content

Modeling Multiprocessor Systems


  • Synchronous Data Flow Graph (SDFG)
    The Synchronous DFG is similar to a directed graph which contains vertices and edges. Where each vertex represents the computation and the edges do the job of carrying the data from one vertex to another
    Vertex is represented by a circle whereas the edge is denoted as an arrow.


  • Homogeneous Synchronous DFG (HSDFG)
    When there is only one token at the input and only one token at the output in a SDFG, then it is said to be Homogeneous Synchronous DFG (HSDFG). Usually SDFG is converted into a HSDFG by making the input and output to have one token, so that there will be lot of small HSDFG created out of SDFG.


  • Acrylic Precedence Expansion Group (APEG)
    APEG is obtained by removing the delay elements from the SDFG. Each vertex takes inputs and giving outputs, if any such inputs contains delay, then the delay has to be removed to obtain the Acrylic Precedence Expansion Group (APEG)

Example for all the above models is given below · The above figure shows the Directed Graph which includes two instructions X and Y which belongs to Processor A (PA) and processor B (PB) respectively.
· The outputs from X are (a, b, c) and two of its outputs are sent to Y as inputs. There are two other inputs i, j are sent to Y. so the total inputs to Y is 4. This is indicated by a circle with 4 as the number of inputs. So this graph is said to be SDFG.
· To convert this in to HSDFG, there should be only one token at the input and output.
· In the above figure, there are two inputs to Y and it is being separated as one input, one from X1 and another from X2. (X1 & Y) makes one HSDFG and (X2 & Y) makes another HSDFG.
· APEG is obtained from removing the delay elements from an HSDFG. In the above figure there is no delay element between (X2 and Y), but there is a delay between (X1 and Y).
· So the following figure is APEG


Comments

Popular posts from this blog

Installing ns-3.34 in Ubuntu 20.04

This post shows how to install ns 3.34 in Ubuntu 20.04 LTS Prerequisites: Fresh installation of Ubuntu Version 20.04 LTS  ns3.34 can be downloaded from here Follow the video link for complete step by step instructions on the installation.  This version fixes the compilation issues of vanet-routing-compare.cc (bug in ns3.33)  Issue the following commands after opening a terminal  $ sudo apt update $ sudo apt install g++ python3 python3-dev python-dev pkg-config sqlite3 python3-setuptools git qt5-default gir1.2-goocanvas-2.0 python3-gi python3-gi-cairo python3-pygraphviz gir1.2-gtk-3.0 ipython3 openmpi-bin openmpi-common openmpi-doc libopenmpi-dev autoconf cvs bzr unrar openmpi-bin openmpi-common openmpi-doc libopenmpi-dev tcpdump wireshark libxml2 libxml2-dev Unzip or untar the ns-allinone-3.34.tar.bz2 in the home folder (in my case its /home/pradeepkumar) $ cd ns-allinone-3.34/ $ ./build.py --enable-examples --enable-tests  Once the installation is completed, you may get an output show

Installation of ns3 in Windows 10 and Windows 11 OS using WSL (Windows Subsystem for Linux)

This post shows how to install ns-3.33 in Windows 10 through WSL (Windows Subsystem for Linux) This posts works for Windows 11 also (I have tested it on a Windows 11 ISO and it works the Same way as mentioned in the following post.) This post will work for ns-3.3x version. Prerequisites : Install Windows Subsystem for Linux with GUI: Please refer the following video  System Information: OS used: Windows 10 and WSL (Ubuntu 20.04) GUI: XServer for Windows NS3 Version: ns-3.33 See the following complete video on how to install ns3 in Windows 10 Step 0 : Open XLaunch Step 1 :  Open WSL using PowerShell and open it as Administrator Command:/  wsl $ xfce4-session The GUI of Ubuntu Opens within Windows 10 OS. Step 2 : Download ns3 from nsnam.org website through Mozilla Firefox browser Step 3: Open a Terminal  $ sudo apt update $ sudo apt install build-essential autoconf automake libxmu-dev python3-pygraphviz cvs mercurial bzr git cmake p7zip-full python3-matplotlib python-tk python3-dev qt5-q

Installing NS-3.32 in Ubuntu 20.04

This is about installing ns version 3.32 in Ubuntu 20.04 LTS. #ns3 #ns3 .32 #networksimulation The commands used in the video are given here. $] sudo apt update $] sudo apt install build-essential autoconf automake libxmu-dev python3-pygraphviz cvs mercurial bzr git cmake p7zip-full python3-matplotlib python-tk python3-dev qt5-qmake qt5-default gnuplot-x11 wireshark Download the ns-allinone-3.32.tar.bz2 package from nsnam.org and copy it to /home/ folder See the full video for detailed instructions Extract it either in GUI or using command $] tar jxvf ns-allinone-3.32.tar.bz2 $] cd ns-allinone-3.32/ $] ./build.py --enable-examples --enable-tests The above command will take some time to install all the packages  You can see the output as shown below ns3 To check whether ns3 installed successfully, use the following commands. $] cd ns-3.32/ $] ./waf --run hello-simulator You should get the output as Hello Simulator $] ./waf --run first This is the example from the ns-3.32/exa