1. July 29 th, 2006 M. van Veelen J.Bregman1 Failing scaling and Roadmapping to new Architectures Can we use the existing architectures with new and future technology for the next generations of processing machines in Radio Astronomy? Martijn van Veelen & Jaap Bregman

2. July 29 th, 2006 M. van Veelen J.Bregman2

3. July 29 th, 2006 M. van Veelen J.Bregman3 Spatial multiplexing (partition antennas) FAILING SCALING

4. July 29 th, 2006 M. van Veelen J.Bregman4 Spectral multiplexing Transpose FAILING SCALING

5. July 29 th, 2006 M. van Veelen J.Bregman5 Scaling chip design principles It is hardly possible to synchronize the processing. Different areas on chip operate on their own decoupled clock. In order to achieve low power/cm 2 we no longer push to run a maximum chip clock

6. July 29 th, 2006 M. van Veelen J.Bregman6 Coherent = synchronous processing? FAILING SCALING

7. July 29 th, 2006 M. van Veelen J.Bregman7 The emerging router FAILING SCALING

8. July 29 th, 2006 M. van Veelen J.Bregman8 Beamforming and two-step DFT FAILING SCALING

9. July 29 th, 2006 M. van Veelen J.Bregman9 log(#antennas) log(computations) F X break-even point O FX = O XF WSRTALMALOFARSKA FAILING SCALING

10. July 29 th, 2006 M. van Veelen J.Bregman10 32bit 2 3 ? ? 703134291.5 70312542915.3 70-700MW FAILING SCALING Required FX operations

11. July 29 th, 2006 M. van Veelen J.Bregman11 Trends in the correlator architecture Spatial correlator function no longer determines the geometrical layout The technology (chip-speed) no longer determined the geometrical layout Coherent correlation is no longer implemented by synchronouns processing The connectivity between correlator and calibration is a priority driver rather than the input of the correlator.  Function and technology are no longer determining the architecture  The power consumption / cooling and the correlator output connectivity drive the architectural optimizations.

12. July 29 th, 2006 M. van Veelen J.Bregman12 technology ? architecture function ? ? Function  Form

13. July 29 th, 2006 M. van Veelen J.Bregman13 technology ? ? ? function Function  Form FPGACPU FXXF Round robin XF Spatial nulling Spectral blanking

14. July 29 th, 2006 M. van Veelen J.Bregman14

15. July 29 th, 2006 M. van Veelen J.Bregman15 Time-To-Market

16. July 29 th, 2006 M. van Veelen J.Bregman16

17. July 29 th, 2006 M. van Veelen J.Bregman17

18. July 29 th, 2006 M. van Veelen J.Bregman18 technology HW platform SW platform Processing software function COTS HW NRE reliability TCO Application Specific Power consumption maintenance system costs (manufacturing) lifecycle flexibility

19. July 29 th, 2006 M. van Veelen J.Bregman19 What is effective R&D? The development paths for existing correlators based on Hero-approach vs. the just-in-time integration approach.

20. July 29 th, 2006 M. van Veelen J.Bregman20 The Hero-approach

21. July 29 th, 2006 M. van Veelen J.Bregman21 The just-in-time integration approach

22. July 29 th, 2006 M. van Veelen J.Bregman22 Optimal R&D effort (time x man-power) R&D effort Resource Optimized Platform HW-centric Control Software Aging Technology R&D effort COTS Correlator Platform Operating System R&D Processing Software Manufacturer Effort (Multi-Customer)

23. July 29 th, 2006 M. van Veelen J.Bregman23 System Costs Development Time WSRT LOFAR SKA ?

24. July 29 th, 2006 M. van Veelen J.Bregman24 Roadmap architecture time Function Architecture Technology

25. July 29 th, 2006 M. van Veelen J.Bregman25 Roadmap Functions Architecture Technology time XFFXFFXFFX ? synchronousasynchronous round-robin scheduling Gb routers Infiniband switches 4D torusRing networkfanout Multi-core FPGA Multi-core microproc ASIC gate arrays FPGAs Micro proc F X power consumption maintenance availability Operating Modes survey speed serendipity flexibility 130nm90nm? nm sensitivity ? Crossbar ? Emb.Mult. FPGA AdvancedTCA

26. July 29 th, 2006 M. van Veelen J.Bregman26 Conclusions Architectures emerge but not in a predictable manner. Technology advances stepwise rather than continuously, it can’t be predicted on a timescale of half a decade. Given the emerging optimization criteria related to TCO, a one-to-one scaling of existing architectures will fail. The technology advances with Moore’s Law are not sufficient to provide a suitable architecture for SKAs central processor. We can benefit from platform-specific R&D invested by industrial machine manufacturers, if we pursue shorter TTM. Considering the development paths of processing machines so far, this indicates the need to shift our R&D focus Roadmapping helps to address the key issues on the right level of abstraction, somewhere in between the function and technology.

27. July 29 th, 2006 M. van Veelen J.Bregman27 Failing scaling and Roadmapping to new Architectures Can we use the existing architectures with new and future technology for the next generations of processing machines in Radio Astronomy? Martijn van Veelen & Jaap Bregman