1. SJ – Sept 2004 1 Future processors: What is on the horizon for HEP computing Sverre Jarp CERN openlab CTO IT Department, CERN

2. SJ – Sept 2004 2 Items to consider Processors will offer: 64-bit pointers (and long ints) Little growth from pure GHz “Multi-core” designs as a compensation More and more heat ! Systems will offer: Heterogeneity ? Growth through Brain, not Brawn Various form factors Units of one Mega-SPECint-2000

3. SJ – Sept 2004 3 Processor considerations

4. SJ – Sept 2004 4 64-bit computing Are your codes 64-bit clean? If not, convert NOW !! All  -processor families are now 64- bit capable AMD Athlon-64/Opteron (AMD64) IBM Power family (also MAC G5) Intel Itanium Intel Prescott/Nocona (EM64T) SUN Sparc

5. SJ – Sept 2004 5 Single processors In the past there were rapid uni- processor speed increases Between 2000 and 2003 we saw spectacular growth rates: ACGR: ~40% Slow growth since then Global SPECint number can be helped by other factors, however. Bigger caches, faster buses, improved compilers have helped produce 40-50% increase over the last two years: ACGR ~20% 90 nm is not helping raw clock speed much Same issue for all three: AMD, IBM, Intel

6. SJ – Sept 2004 6 Multi-core designs Moore’s original law said: We are “Cramming more components onto Integrated Circuits” Article published in 1965 (Almost 40 years ago) The good news: We still are! Transistor count still grows Best way to put them to use Multiple processors on a die: 1  2  4  … Great news for HEP’s “trivial paralellism” But, systems will become more complex A dual-socket 4-way CMP server may require 8-16 jobs in flight !!

7. SJ – Sept 2004 7 Heat issue Big surprise to the whole industry? Processors are getting hot Many mainstream processors are in the range 90 – 135 W Fortunately, some processor designs have focused on low power These may serve as design examples for hotter cousins (in the future) Nevertheless, the problem will not go away Are we prepared to bring water cooling back?

8. SJ – Sept 2004 8 System considerations

9. SJ – Sept 2004 9 Heterogeneity Unavoidably, our grids will have to cater with heterogeneous architectures Mainstream Linux/GNU support may become the common denominator 32-bit only x86 processors 64-bit capable x86 processors Itanium processors IBM Power5 systems All have Red Hat/Suse server support

10. SJ – Sept 2004 10 Brain, not brawn Increasingly important to extract performance from whole system  -architecture CMP designs (as discussed) Cache hierarchy and bus designs Operating system scalability Compiler cleverness Middleware optimization Application optimization Smartness required at all levels

11. SJ – Sept 2004 11 System form factors Our beloved DP (read: Dual Socket) systems may go out of fashion, in favour of: 1) Single-socket (still multi-processor) systems 2) Racks full of game systems ? HEP needs to understand the implications of new efforts, such as the nVIDIA graphics or the Sony/Toshiba/IBM cell processor 3) Larger servers For instance: 4 sockets with 4 processors each 4) Blade-based racks Fully integrated with disks, network I/O, etc. This is an entire “research topic” in itself

12. SJ – Sept 2004 12 “Megaracks” Expect companies in the future to offer “units” of 1 Mega-SPECint- 2000 For instance: 2000 SPECint/core 6 cores/socket 4 sockets/2U 22 2U/rack Maybe our computer centres only need to house a few “hot” racks??

13. SJ – Sept 2004 13 Conclusion LEP experienced 3 distinct “system” cycles Mainframes  RISC systems  Linux PCs Be prepared for deep changes Also during the LHC era

14. SJ – Sept 2004 14 Backup

15. SJ – Sept 2004 15 Are you ready for a 64-bit world ?

16. SJ – Sept 2004 16 Mega SPECint racks ?

17. SJ – Sept 2004 17 Water cooling ??