Presentation on theme: "David Britton – Imperial College 23 September 2005Collaboration Meeting Tier-1 Planning Version-35 David Britton Imperial College."— Presentation transcript:
David Britton – Imperial College 23 September 2005Collaboration Meeting Tier-1 Planning Version-35 David Britton Imperial College
David Britton – Imperial College 16/Jan/06Tier-1 Board Inputs: Money GridPP1 Hardware – £2,314K Final out-turn now thrashed out with CCLRC. Less than previously reported because some money spent from the Hardware budget on other items such as staff costs, travel, overheads and general GridPP operations costs. GridPP2 Hardware – £2,999K This is increased slightly from previously reported due to slow hires at CCLRC. This number will continue to fluctuate at the 10% level because it effectively includes the contingency - E.g. Tier-2 depreciation (there is currently 135K further savings from CCLRC posts but not added to HW budget). Profile The current model contains a profile which includes the current capacity purchase and a first stab at planning for Tape to be described later. There is slightly more bias towards disk since it is hard to over-allocate.
David Britton – Imperial College 16/Jan/06Tier-1 Board Input: Hardware Costs from Andrew Sansum 2/Aug/05: Mid K/TB (recent quotation for small system with 400GB drives - 12 port PCI/RAID) (assume in early GB drive - 1TB sometime in port PCI/RAID) (linear interpolate ) (linear interpolate ) (informed Guess 1Tb/inch - 3TB drives) From Sep. Meeting:
David Britton – Imperial College 16/Jan/06Tier-1 Board Inputs: New Hardware Costs Disk costs are 33% more than expected CPU costs are 50% more than expected
David Britton – Imperial College 16/Jan/06Tier-1 Board Outputs: Tier-1 Capacity Tier1Plan29 Tier1Plan35 ~25% reduction in Disk and CPU
David Britton – Imperial College 16/Jan/06Tier-1 Board Output: TDs LCG Pledge Table + Errors RAL, UK PledgedPlanned to be pledged CPU (kSI2K) Disk (Tbytes) Tape (Tbytes) /- 10% +/- 20% +/- 30% +/- 40% +/- 50%
David Britton – Imperial College 16/Jan/06Tier-1 Board Nominal Fair-shares as a fraction of Request For the LHC experiments and BaBar, the orange boxes are where we would fail to meet (80%) of International MOU commitments.
David Britton – Imperial College 16/Jan/06Tier-1 Board ADS Planning - Requirements 0.4?<0.8<2.0 Service Challenge? Guess 50% of the new Robot populated with TK10 tapes provides 2.3PB Current six 9940B drives deliver 150MB/s. Bandwidth of new drives uncertain. Is it worth doing service challenge on old kit?
David Britton – Imperial College 16/Jan/06Tier-1 Board Disk/CPU/Tape
David Britton – Imperial College 16/Jan/06Tier-1 Board BaBar Argue for increase in resources from fair-share level: - to honour International MOU commitments. - to prevent Tier-A from being downgraded to a Tier-2. - to prevent UK physicists being disadvantaged. - to preserve/recover UKs international reputation. - to enable common fund rebate (but $460k is hard to understand). - Babar has real data. Fair enough, but buying an extra 100TB of disk now means ~ TB less disk can be bought for 2008: - CMS/ATLAS already failing to meet MOU commitments from CMS Tier-1 will be downgraded to a Tier-2. - UK physicists will be disadvantaged. - UKs international reputation will be damaged. - Unknown common fund implications. - LHC will have real data.
David Britton – Imperial College 16/Jan/06Tier-1 Board BaBar My opinion: The only argument is a pragmatic one: BaBar has a problem right now which could be solved. Bringing spend forward compounds a problem that already exists in 2008 so it would be better to squeeze the LHC this year and manage within the currently planned capacity. Note that we have already mortgaged the real-data takes precedence argument because there is no significant allocation for the large Linear Collider or Neutrino communities in the present planning so in 2008 there is already no possibility of applying this argument. If funding is bought forward, then I believe the minutes should record the principle on which the decision was made. We are going to be in the identical situation next year (BaBar request is >300TB) and the year after with the LHC experiments.
David Britton – Imperial College 16/Jan/06Tier-1 Board Issues The latest purchase prices for Disk and CPU both cause a considerable shock to the planning and jeopardise the LCG MOUs. Uncertainty in demand for Tape and risk of delays commissioning Castor2 suggest that we move cautiously to the new Robot. Would like an affordable plan that maintains 9940 infrastructure until milestones can be met with the TK10/Castor2 installation. The BaBar issue is a close analogy to the situation foreseen with the LHC experiments, particularly CMS, in The issues are coupled. The next purchase.