1. CERN les.robertson@cern.ch 25-Mar-99 Computer architectures and operating systems How many do we have to support in HEP? HEPCCC meeting CERN - 9 April 1999 Les Robertson CERN/IT

2. CERN 25-Mar-99 - #2les robertson - cern/it Summary  A claim that PCs with Linux and Windows are enough for all of HEP’s needs  An assorted collection of caveats  A suggestion that HEP needs to begin to standardise platforms now, to ensure that we all have the same history when decisions for LHC are made  A proposal for how to begin

3. CERN 25-Mar-99 - #3les robertson - cern/it What is likely to happen over the next few years?  PC hardware  cheapest, best price/performance, as fast as is needed  Windows ----> Windows 2000  consolidating its 100M unit market  Linux establishing itself as  by far the biggest ever Unix  the standard for Intel architecture  Hard times for the RISC vendors

4. CERN 25-Mar-99 - #4les robertson - cern/it The Platform  PCs are and will remain (one of the) best price/performers for HEP codes  They may not be the fastest, but they will be fast enough  Reliability and support are as good as for RISC systems  even when buying from small European assemblers  PCs get us into the REAL COMMODITY market, with benefits like -  standard products  competitive pricing & support  multi-sourcing (of a sort)  choice of operating systems

5. CERN 25-Mar-99 - #5les robertson - cern/it The Platform - II  A real choice of operating systems - with two complementary environments:  Windows for -  productivity tools  engineering applications  mass market leverage  Unix (Linux) for -  server strength  scalability  preferred physics environment  legacy applications (and experience!)  (support of multiple architectures - but is that what we want?)

6. CERN 25-Mar-99 - #6les robertson - cern/it The Platform - Conclusion  PCs with Linux and Windows are just fine  price  reliability  usability & functionality  support  Why would we need to support anything else?

7. CERN 25-Mar-99 - #7les robertson - cern/it

8. CERN 25-Mar-99 - #8les robertson - cern/it The other side of the coin RISC hardware and software provide -  Solid, reliable hardware, designed to maximise performance  Industrial strength operating systems  clear functionality spec  performance-tuned  multi-processor tested  deterministic support, with clear escalation process  Certified hardware + software combinations  Focus on system (as opposed to component) design  and willingness to discuss product strategy, requirements, joint developments, etc. with HEP labs (or is that just a marketing ploy?)

9. CERN 25-Mar-99 - #9les robertson - cern/it Does Java change the landscape?  SUN, Oracle, etc. propose light-weight Java stations  Really low cost, with zero administration  All the applications are down-loaded as needed  Generally, there is a thin client, with all the smart stuff executing on a server.. but everything has to be written in Java  Good for applications which naturally require a central server (e.g. database applications), or are naturally distributed (e.g. Web browsing)  Not so obvious for applications that do not have a natural client-server model, and/or use multiple languages (like most HEP applications)  There is some argument about Java being more portable than other languages ………… and there are other positive aspects of it as a language

10. CERN 25-Mar-99 - #10les robertson - cern/it Does Java change the landscape?  low cost Java stations will keep up the pressure on Wintel  but otherwise, for HEP applications and HEP users …. …… NO

11. CERN 25-Mar-99 - #11les robertson - cern/it Is Linux ready for HEP?  Linux and the rest of Free Software offer:  high quality design  excellent functionality  the products of massive intellectual investment  a sustainable environment - it’s “free” because the development & support are contributed by the user community, not because the developers do not get paid  The functionality as a desktop system, or simple server are fine ……… but many proprietary Unix systems have much better server functionality ……… however, the evolving farm models place limited requirements on data servers  Linux tape and disk server evaluations at CERN look promising

12. CERN 25-Mar-99 - #12les robertson - cern/it Is Linux ready for HEP?  Support is still a problem  especially for load-related, configuration-related issues on servers But there is a rapidly growing number of commercial offerings (including IBM+Red Hat, HP+Red Hat) and HEP could probably justify a kernel programmer or two (since there is no licence fee for the OS)  Lacking third party products  or well-supported ports of third party products (and in particular Objectivity)  changing fast - but this is clearly still a concern

13. CERN 25-Mar-99 - #13les robertson - cern/it Is Linux ready for HEP? Not quite for all applications, but it looks very promising

14. CERN 25-Mar-99 - #14les robertson - cern/it Are we sure that Linux is the right choice for Unix on Intel?  No - we cannot be sure there will be competition from the suppliers of proprietary Unix (Compaq, IBM, HP) Linux is the clear and growing leader today - it will be hard to beat

15. CERN 25-Mar-99 - #15les robertson - cern/it Do we also need Windows?  The majority might say No  Windows is hard to use for physics batch, especially when we try to make it look like Unix  It probably is not much better (maybe even worse) as a server than Linux  Support for complex environments is not any clearer  But there are so many excellent “productivity” tools and applications sustained by the 150 million unit Windows market  How can people get by without Developer’s Studio?  How can Star Office keep up with MS Office?  ……….  How can we ignore the biggest ever operating system, just as the various versions come together in Windows 2000?

16. CERN 25-Mar-99 - #16les robertson - cern/it Did we forget about the Mac option? No, it is not really an option Or is it?

17. CERN 25-Mar-99 - #17les robertson - cern/it An opportunity for standardisation in HEP  We (HEP) are running far too many operating systems, in many cases with only slightly different functionality or hardware cost benefits - - and at a high cost for users and support teams  PCs + { Linux ¦ Windows } offer an historic opportunity to reduce the solution set  The requirements of LHC computing -  massive numbers of processors/boxes  integration of regional computing centres and CERN demand a common agreement on what will be supported  We need to start the dialogue now, to avoid the old problem of history dictating our choices requirement

18. CERN 25-Mar-99 - #18les robertson - cern/it Proposal for a policy  Restrict ourselves to PC hardware  with Linux or Windows 2000  Develop a migration plan -  progressively freeze support for other Unixes, announcing end-dates which are reasonable for old experiments,  but discourage strongly further investments in RISC systems by current and future experiments  Beef-up investment in Linux and Windows  bring support up to the standards of proprietary Unixes  tackle the problems of scaling the management and performance of desktops and physics farms  engage HEP in the community  emphasise the importance of minimising differences between HEP labs  Focus on the Web as the user interface

19. CERN 25-Mar-99 - #19les robertson - cern/it Just to be clear ----  This is a proposal for a convergence policy  which looks realistic now  and will provide a single starting point for LHC computing  but we can be sure that the business will not stand still, and we shall sooner or later have to expand the systems and architectures supported AIX WNT Irix Solaris Digital Unix HP-UX MAC-OS Linux Windows 95 SPARC MIPS Intel IA-32 PA-RISC Power PC Alpha Linux Windows 2000 Intel IA-32/64 - - - ?

20. CERN 25-Mar-99 - #20les robertson - cern/it Conclusion  PCs, Linux and Windows 2000 enable a major simplification of the environments supported for HEP, where our needs mostly coincide with those of many other users  We should take the decision to standardise on these within HEP - following and stimulating the mass market in most cases - restricting HEP specials to really, really special issues  And we should start talking now about how LHC computing centres evolve to a standard approach which enables them to work with each other