CCRC'08 F2F meeting
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Europe/Zurich
IT Auditorium (CERN)
IT Auditorium
CERN
Description
Agenda
EVO room CCRC08 in WLCG Community
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09:30
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09:45
Summary of F2F meeting of 10 January 2008 15mSpeakers: Harry Renshall (CERN), Jamie Shiers (CERN)Executive Summary of CCRC08 Face to Face meeting of Jan 10 2008 The agenda with attached documents is to be found at: http://indico.cern.ch/conferenceDisplay.py?confId=24844 The meeting was chaired by J.Shiers with notes taken by H.Renshall. Attendance: Representatives of all experiments and Tier-1 sites were present in person or by teleconference apart from NDGF. The chairman proposed "official" dates for the Feb run of 4 Feb till 29 Feb inclusive and of 5 May to 30 May inclusive for the later run. The later experiment presentations expand on the details but in summary for the February run: LHCb would do pre-testing from 4 to 17 Feb then try to reach their full rate for the next 2 weeks. ATLAS are running a Tier-0 test from 4 to 10 Feb so will start ccrc08 from 11 Feb. ALICE plan to run for the whole period as resources allow. CMS will be performing functional tests at rates comparable to CSA07. Their tests are largely independent but should be performed in parallel where possible with, in particular, many to be scheduled together with the other experiments to reach the scale of a full stress test. There was discussion on which middleware versions to use as there are still changes in the pipeline. There are EGEE Engineering Management Taskforce (EMT) meetings on this on Mondays and Wednesdays. The chairman requested that the next meeting document the current production middleware versions and those fixes in the pipeline with the week of 21 January being regarded as the last realistic date for any changes. P.Fuhrman of dcache said that he had some minor dcache issues pending but understood the deadline. All Tier 1 would then be requested to deploy the same versions. There was then a discussion on how to handle any fast-track fixes as these would normally require at least a weeks elapsed time to process. O.Keeble said these would receive top priority from the EGEE team during ccrc08 and pointed out that once rpm's are released sites could choose to deploy them. A complication is that such releases tend to also contain other changes. The concensus was that fast-track fixes will be dealt with on a case by case basis. The experiment requirements were then presented (see attached material) with some follow-up discussion. LHCb presented cpu requirements assuming 100% efficiency while CERN only sees 40% for them even though they prestage their data. J.Gordon of RAL estimated they would need 500 job slots there but thought they should offer 700. LHCb will need storage elements under srm 2.2 configured with correct space tokens. They will add a directory structure into their plans and were requested to indicate how much space would be behind each one. None of their February data needs to be kept. CMS have not yet written down their detailed requirements in the LHCb style but they will be similar to last years CSA07. They would like to be able look at the performance of worker nodes running concurrent software from several experiments. They have no serious plans to use space tokens having mainly T1D0 type data. ATLAS plan to use full physics simulated data aiming at a daily 10 hour 200 Herz duty cycle. The first pass reconstructed data at CERN will not go to tape. In preparation for the May run they will need 3 months of Monte Carlo production at twice the current rate. ALICE will have a workshop on 15-16 Jan where they will decide on their target rates and metrics. They expect to want to keep about half of their raw data (i.e. that coming from the detector). At the end of the presentations the chairman reiterated the desire for a similar numerical presentation of requirements to that given by LHCb. In a session on monitoring it was proposed there be a run coordinator for each experiment looking at gridview, SAM and experiment monitors. Several Tier 1 said they would like more interaction with the experiments when problems were detected. There was a somewhat fragmented review of the SRM v2 production status. Conclusions were that all dcache sites must enable space management with target the end of next week and T1 spaces per token and experiment should be configured by the end of the following week i.e. by 25 Jan. All experiments should use at least one space token with SRM v2. On metrics the conclusion was experiments should write down their targets for themselves and for their Tier 1 by 21 January. The presentation on tape staging showed the strong coupling between drive transfer rates and file sizes and hence small files on tape must be avoided. Sites were requested to record key statistics during the February run such as file sizes and tape remount rates. It is clearly important to test concurrent tape writing by all experiments at the tape custodial sites. The final discussion was on future meetings and reporting mechanisms. The weekly conference call at 17.00 on Mondays will continue until February with a pre-GDB Face-to-Face meeting from 1 to 4 pm on 5 Feb. There will be a new short daily meeting at 15.00 (except Monday) starting Jan 15 and which should produce a few lines summary of current problems and status. This would be intended to complement the experiment operations meetings and make sure the right people shared common timely information. This model can be evolved as proves necessary.
- 09:45 → 10:00
- 10:00 → 10:15
- 10:15 → 11:00
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11:00
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12:30
Baseline storage management versions: known features & outstanding bugs 1h 30m
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12:30
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13:30
lunch break 1h
- 13:30 → 14:30
- 14:30 → 15:30
- 15:30 → 16:00
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09:30
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09:45