Projects (USIU)
Project: Pi Based Cluster
Course: DST4030 - Parallel Computing
Members
- Waituru Mwangi
- Mercy Nekesa
- Frank Rutahiwa
- Bruce Kwiringira
- Joseph Manywanda
- Hungai Kevin
- Trevis Sinatra
About:
In this project, we will build a cluster of identical raspberry pi nodes, networked together and running parallel processing software that allows each node in the cluster to share data and computation.
Objective(s):
Building a cluster computer powered by raspberry Pi that could be used to develop and run parallel and distributed programs. In doing so, the following goals could be achieved.
Practical understanding of building parallel systems.
- Experiment with different configurations to achieve better performance.
- Familiarity with MPI (Message Passing Interface) API for parallel programming.
- Familiarity with raspberry pi micro computers useful for rapid hardware prototyping.
Building the system:
Components:
- Raspberry Pi Model B
- Storage - SD cards
- Ethernet cables
- Power supply
- Linux OS
- There is an array of different possibilities.
- MPI library
- MPICH or OpenMPI
- Ethernet switch and Router
- A switch that we can use without interruption during the lab works.
Implementation:
Ideally the project will be implemented in stages, starting with configuring the first two nodes and then scaling to add all other additional nodes.
Resources:
There are many resources that we will use including Raspberry Pi Foundation https://www.raspberrypi.org/
Prof Simon Cox, Making a Raspberry pi super computer, University of Southampton http://coen.boisestate.edu/ece/raspberry-pi/
Configuring the nodes, step by step guide
- First, configure the first node
When this is done, its easier to clone as many nodes as wanted.
1. Get the OS image raspberrypi.org/download
After many false starts, we were content to just use Rasbian Weezy 5.5
2. Get image into a the sdcard
On Linux:
#dd if=/media/yourMachine/Images/2015-05-05-raspbian-wheezy.img of=/dev/sdb bs=512 conv=noerror,sync
3. Boot the Pi
Great suspense it anything did not go as planned.
If there is an error with the card or any other thing, nothing will show up on the screen, if the Pi is overwhelmed it will take forever to boot. Rasbian is ideal because it has been tested and has a descent first boot time.
4. Configuration on first boot
These configurations can be done later with raspi-config or ideally done on the first boot.
- Expand image to fill card
- Change the password
laxmi
• Change hostname (node1 or nodex)
5. Re boot
user: pi (has root priviledges) password: laxmi
Refresh update repo packages and update the software
#sudo apt-get update && sudo apt-get upgrade -y
Choose your poison: I prefer having my emacs
#sudo apt-get install emacs
you only get version 23, will have to compile to use version 24)
6. Refresh and update the softwares, if not done yet.
#sudo apt-get update && sudo apt-get upgrade -y
7. Get Fortran, (strange but we need it)
#sudo apt-get install gfortran
8. Before getting Argonne MPICH
Resource: http://www.mpich.org/documentation/guides/
The have great resources not just the the MPICH library
#mkdir /home/pi/mpich3 $ cd ~/mpich3
9. Get MPICH sources from Argonne
#wget http://www.mpich.org/static/downloads/3.1.4/mpich-3.1.4.tar.gz
Resource: http://www.mpich.org/downloads - Get latest stable
10. Unpack them.
#tar xfz mpichXXX.tar.gz
11. Planning a clean place for install
#sudo mkdir /home/rpimpi/
#sudo mkdir /home/rpimpi/mpich3-install
12. Make a build directory, and go to the build
#mkdir /home/pi/mpich_build $ cd /home/pi/mpich_build
13. Configure the build
This will take a while, you can get the cards ready, you can play while the configurations takes place.
#sudo /home/pi/mpich3/mpichXXX/configure -prefix=/home/rpimpi/mpich3- install
14. Make
What ever it took the last, you can +1
#sudo make
15. Install the files
It can take a bit of time, but not any way close to the last two stages.
#sudo make install
16. Add the place that you put the install to your PATH
#export PATH=$PATH:/home/rpimpi/mpich3-mstall/bin
17. Or Note to permanently put this on the PATH you will need to edit .profile
#emacs -/.profile
and add lines below:
#Add MPI to path (This is just a comment for later) PATH="$PATH:/home/rpimpi/mpich3-install/bin"
18. Verify if the install were succesful
#which mpicc /home/rpimpi/mpich3-install/mpicc $ which mpiexec
19. Go /home and set a place for your first test
#cd ~
#mkdir mpi_first_test $ cd mpi_first_test
20. Now testing MPI on single node
#mpiexec -f machinefile -n <number> hostname
where machine file contains a list of IP addresses (in this case just one) for the machines
21. How this supposed to be done
a) Get your IP address
#ifconfig
b) Put this into a single file called machinefile
#emacs machinefile
c) Add this line:
192.168.1.161 [or the ip is ... ]
22. Now test if the machinefile
# mpiexec -f machinefile ~n 1 hostname
Output should be: node1 ('hostname')
23. Little C code using MPI on Pi to calculate Pi
Don't worry, we shall not write the c code our selves, but MPICH has some example codes we can run.
# cd /home/pi/mpi_fist_test
# mpiexec -f machinefile -n 2 /home/pi/mpich3/examples/cpi
Output is should be
Process 0 of 2 is on raspberrypi Process 1 of 2 is on raspberrypi
pi is approximately 3.141 5926544231318, Error is 0.0000000008333387
24. Celebrate!
This calls for a celebration! (Seriously!)
25. Shut down
# sudo poweroff
