Making progress with the Cell Broadband Engine

Changelog

Introduction

Two STI Cell platforms are available in the course: The CellBuzz installation at the Georgia Institute of Technology, and a Sony PS3 known as Dark (dark.ucsd.edu), which is located in the CSE Department. To get an account on CellBuzz, go to the web site and fill in the on-line account request form. Contact Professor Baden if you need an account on Dark.

Getting started with CellBuzz

Login to the front end of CellBuzz at cell-user.cc.gt.atl.ga.us There is a User’s guide at http://wiki.cc.gatech.edu/cellbuzz/index.php/User_Guide

I’ve installed some code in ~baden/cse260_wi08, which used in a Cell workshop held at UCSD last May.

Not all the examples will compile on CellBuzz, but the following applications have been verified to run:

Build the 3 versions of hello, and run: hello_ppu, hello_spu, hello_be1-sync as ./hello_ppu and so on. Run in interactive mode, which you enter by typing

Important: when you run in the interactive queue, you are locking down the resource for your exclusive use, so be mindful of others.

To build the other applications, you’ll need to make a small patch to the last line of each Makefile (Be sure and look in the ppu and spu spu subdirectory). Replace the following line

with the contents of the file ~baden/cse260_wi08/FixMakefile

Some sample tutorial code is also located in

To get sdk materials compiling, you need to setup your ~/.cshrc, by making sure the first line is as follows. #!/bin/tcsh

Also set up this enviroment variable

setenv CELL_TOP /opt/ibm/cell-sdk/prototype/

Lastly, do (or .tcshrc if you use tcsh).

chmod +rx ~/.cshrc

To get the simple tutorial running:

cd ~
mkdir tutorial
cd tutorial
cp -r /opt/ibm/cell-sdk/prototype/src/samples/tutorial/simple .
cd simple

Edit the Makefile and set

INSTALL_DIR = ~/tutorial/simple

Now, make should work.

To run, start an interactive session by invoking qsub -I. Then cd into tutorial/simple and do ./simple

There is a step by step spu-ization in /opt/ibm/cell-sdk/prototype/src/samples/tutorial/euler

I’ve also installed a small application, Dot, that computes the dot product. This application illustrates the definition of control blocks, the use of DMA (with double buffering), vectorization, and various other details. Note that the Makefile includes references to the library and header file to libmisc which is needed to ensure that the aligned malloc and free are available.

Examining the code, you’ll notice that spu threads are spawned a bit differently than in the provided examples. The control block is transmitted using mailboxes. Various other details differ as well. Choose a style that suits you. There are different ways of realizing the same goal.

Where to look for documentation

There is an extensive array of documentation, articles, and reading materials at the Cell Broadband Engine resource center (IBM). Within this site are two concise documents that will help you get started:

Two other documents are also useful:

Lastly, here is a link to An introduction to the IDE for the Cell Broadband Engine SDK by Sean Curry at IBM.

Other resources

Using SDK3.0

The current version of the Cell SDK is 3.0. CellBuzz runs with both 2.1 and 3.0; however, if you want to use 3.0 you must cross compile elsewhere and upload the executables to CellBuzz. A local installation has been set up on cseapel07.ucsd.edu. If you don’t have a CSE graduate student account, let me know.

To run with 3.0 on Cellbuzz, specify the PBS argument -q cellq30. This will work interactively as well, i.e. qsub -I -q cellq30.

Remember, you need to have a local installation of the SDK in order to compile.

To determine which version of the SDK you are using, you must successfully run one of the commands:

Dark is currently running version 2.1, but we are in the process of upgrading it.

Maintained by

baden

@

ucsd.

edu

[ Wed Feb 13 22:17:13 PST 2008 ]