Resource: LCA13 Name: Exploiting ARM GPU resources in Open Source Software Date: 07-03-2013 Speaker: Tom Gall

1. GPGPU ON ARM
Tom Gall
tom.gall@linaro.org

2. SESSION GOALS
• What activity should Linaro
pursue?
• What open source projects
should we work with?

3. BOUNDARIES
• Lets not do any PHD dissertations
• Output must be open source
• Optimized stack should of course advance member goals

4. PARALLEL COMPUTING
Granularity
•
NEON
Grid
OpenStack
MPI/OpenMPI OpenMP/pthreads
Multi-machine Single machine

5. OPEN CL
• Originally proposed by Apple
• API for using your resources including the GPU as a general
purpose power house
• Khronos standard (holders of OpenGL)
• Open Compute Language
• ANSI-C99 w additions
• Open = anyone can implement

6. HSA
• Heterogeneous System Architecture
• hsafoundation.com
• HSA standards out for review
• A better OpenCL
• Better debug, HSAIL

7. QUALITIES IN A CANDIDATE
• Task parallelism
• Break up task over threads
• Data parallelism
• Same operation over lots of data
• Big wins for computationally significant data parallel algs
• Bad
• Lots of pointer chasing
• Calculations that require lots of communication or result dependent

8. PROJECTS
• Libjpeg vs libjpeg turbo
• SQLite
• Hadoop - map reduce
• HipHop?

9. LIBJPEG
• Software, NEON, OpenCL comparison possible
• Android & Linux
• code.google.com/p/jpeg-opencl/source/checkout

10. SQLITE
• Cuda (nVidia only)
• Implemented subset of SQLite vm on gpu
• Pbbakkum.com/db
• Claim of 20x-70x
• Source available, we could port to OpenCL

11. HADOOP
• MapReduce is a major piece of Hadoop
• http://ieeexplore.ieee.org/xpl/articleDetails.jsp?
reload=true&arnumber=6227786
• Measured 1.6-2x improvement
• Used jocl (java bindings for OpenCL)
• Source?

12. PIGLIT
• Mesa test suite
• Includes a number of OpenCL tests
• Should be fairly straight forward to add to LAVA
• Linux
• Android

13. GRAND CENTRAL
• libdispatch - open source
• http://libdispatch.macosforge.org
• Can go hand in hand with OpenCL
• Needs llvm, libkqueue, blocks runtime

14. MORE?