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Hi Gordon, I completely agree with that 1-job 1-core is not going to work for long. Memory cost is dominating. We ride a slower Moore's law. We need to uitlize multiple cores per job, like one single faster CPU. I have been pushing ATLAS but there is not much action. Processing several clusters or tracks in parallel can be problematic -- they may have overlapping hits. Processing events in parallel shuld be physics safe. I have also pushed G4 (core) without success. Cheers. Charlie -- Charles C. Young M.S. 43, Stanford Linear Accelerator Center P.O. Box 20450 Stanford, CA 94309 [log in to unmask] voice (650) 926 2669 fax (650) 926 2923 CERN GSM +41 76 487 2069 > -----Original Message----- > From: [log in to unmask] > [mailto:[log in to unmask]] On > Behalf Of Gordon Watts > Sent: Wednesday, July 25, 2007 2:15 AM > To: atlas-sccs-planning-l > Subject: RE: Agenda for ATLAS/SCCS Planning Meeting 25th July 2007 > > Hi, > As usual, I'm not at all sure that I can make this meeting > (it overlaps with one of the physics meetings I regularly > attend). But, I thought I'd add my two cents worth. > > SLAC may already have a great deal of experience at this -- > but we found that testing modern dual-head 4 core (i.e. total > 8 core) machines took longer than normal. We had to tweak > some Linux OS parameters in order to really get the machine > to run properly. A caveat in this is that we are using this > as a DAQ machine and so we use shared memory to move data > round, and most of what we did had to do with that. But, > none-the-less, I would allow for a longer-than-expected > testing time if SLAC hasn't already had some experience with > these 8 core CPUs. > > I don't know about you guys -- but it is seems to me that > at the rate we are adding cores to pizza boxes our usage > model is going to break down (i.e. one core, one job). It > seems at the straining point right now. > > Cheers, > Gordon. > > > -----Original Message----- > > From: [log in to unmask] [mailto:owner- > > [log in to unmask]] On Behalf Of > Stephen J. Gowdy > > Sent: Tuesday, July 24, 2007 4:50 PM > > To: ATLAS SCCS Planning > > Subject: Agenda for ATLAS/SCCS Planning Meeting 25th July 2007 > > > > ATLAS SCCS Planning 25Jul2007 > > ----------------------------- > > > > 9am, SCCS Conf Rm A, to call in +1 510 665 5437, press 1, 3935# > > > > Present: > > > > Agenda: > > > > 1. DQ2 Status/Web Proxy > > > > 2. Tier-2 Hardware > > > > 3. AOB > > > > Action Items: > > ------------- > > > > 070711 Stephen Find out about benchmarks for CPUs for next > > purchase > > 070718 Not done yet. > >