Draft Agenda for WG meeting, Friday 25 Feb,1400,160-1-009

25 Feb 2000 F Harris Tasks for developing LHCb Computer Model

Draft Agenda for WG meeting, Friday 25 Feb,1400,160-1-009

• Review questions regarding computing model and resources ( first discussion

on our answers) F Harris et al

• Information on GRID EU proposal F Harris

• Update on UK status for LHC computing planning T Bowcock

• Update on other LHCb countries (Germany,France, Italy,.....) (country reps)

• Summary of work needed by WG for the review (summary agreement)


Tasks for LHCb Computing Model Review


Computer Model WG

• Country reps

– Brazil P Colrain(CERN)

– CERN J Harvey(CERN)

– France A Tsaregorodtsev(Marseille)

– Germany M Schmelling(MPI Heid)

– Italy D Galli(Bologna)

– Holland M Merk(NIKHEF)

– Poland M Witek(Cracow)

– Russia I Belyaev(ITEP)

– Spain J Saborido(Santiago)

– Switzerland P Bartalini(Lausanne)

– UK A Halley(Glasgow) T Bowcock will also act on WG (MC Farm)

• Computing group– J Harvey(resources),G Corti(Analysis),M Cattaneo(Reconstruction),M Frank(Databases etc.),

F Ranjard(Simulation),T Cass(IT),F Harris(raw+L2/L3+countries)

• + Anyone who is interested and prepared to help!


Overview of Talk /Discussion

• The questions from Computing Review

• The LHCb data flow model and relationship to MONARC

• A possible ‘tier’ model for LHCb( a la MONARC)

• Spreadsheets for defining our requirements - design and responsibilities

• A current view of a possible LHCb model - some key parameters

• Urgent jobs for country representatives

• SUMMARY of tasks and timescales


The questions posed by the Panel

• What is LHCb Model with respect to MONARC generic model?

• Current thinking re regional centres distribution

• LHCb plans vs. country plans - show consistency

• LHCb and GRID proposals - how , if at all, are we involved

• What are our requirements for storage, processing, communications from now to 2005+, and how will they be satisfied (distribution of tasks in centres)?

• Resource planning from now to 2005+

• Mock data challenges and test-beds?

• Magnetic Tapes vs. Disks (what is our thinking?…)


Some MONARC terminology for Datasets

• Datasets

ESD (Event Summary Data) Output from reconstruction (~ 100 kbyte)cp. Mini-DST

AOD (Analysis Object Data) Basic data for analysis -derived from ESD by Group Analysiscp. Micro-DST (~10 kByte)

DFD(Derived Data) Something smaller than AOD!

TAG Identify event by its physics signature (bits for physics channels or overall event characteristics (~1 kbyte)

cp. Nano-DST

LHCb Computing Logical Dataflow Model

Physics Generator

Detector Simulation

Generator Data

Simulated Raw Data

Monte Carlo

Raw Data

DAQ system

L2/L3 Trigger

Calibration System

Calibration Data

Reconstruction

ESD Event Tags

Raw Data Calibration Data

Group Analysis

Event Summary Data(ESD)

Event Tags

Analysis Object Data(AOD) Group Analysis Tags

Physics Analysis

Ntuples

Analysis Workstation

Physics results

Detector Analysis Cycle

Trigger Tags

Event Tags


MONARC terminology for Tiers• TIER-0 CERN (acts also as TIER-1) Stores all master copies and

does first reconstruction + all or part of re-reconstructions

• TIER-1 large RC on national scale (20% of scale of CERN centre). Can do all functions (e.g. share in re-reconstruction).

• TIER-2 Smaller RC. Essentially dedicated to analysis.

• TIER-3 Institute workgroup servers (for analysis)

• TIER-4 Desktop

COMMENT

TIER-0 and TIER-4 will definitely exist. Combinations of -1,-2,-3 are a matter of system design according to local constraints


The MONARC RC Topology CERN – Tier 0

MONARC report: http://home.cern.ch/~barone/monarc/RCArchitecture.html

Tier 1 FNALRAL

IN2P3622 M

bps2.5 Gbps

622 M

bp

s

155

mbp

s 155 mbps

Tier2 Lab a

Uni b Lab c

Uni n

Department

Desktop


More realistically - a Grid Topology

CERN – Tier 0

Tier 1 FNALRAL

IN2P3622 M

bps2.5 Gbps

622 M

bp

s

155

mbp

s 155 mbps

Tier2 Lab a

Uni b Lab c

Uni n

Department

Desktop

DHL


Tier Facilities• Collaboration centre

– CPU farms

– mass storage

• Tier 1 centre

– 20% of collaboration centre

– CPU farms

– mass storage

– high speed WAN connection to CERN

• Tier 2 centre

– 20% of Tier 1

– CPU farms

– no mass storage

– medium speed WAN connection to CERN

• HEP institute

– local cpu and disk server

– desktop machines


Russia?

MONARC scheme applied to LHCb ( a possible model)

CERN

IN2P3 Lyon DRAL UKITALY?Tier 1

Tier 2/3 LiverpoolOxford Imperial

College

CollaborationCentre

HEP instituteDesktop

Germany?

622 Mbps

2.4 Gbps

Raw Data and L2/L3 (F Harris)

Raw data size and L2/L3 cpu timeUnit Cost

(kSFr) VELO ITrack OTrack RICH1RICH2 PRESH ECALHCALMuonL1Trig TotalNo of channelsEvent Size (kB)L2 cpu time (SI95 secs)L2 data generated (kB)L3 cpu time (SI95 secs)L3 data generated (kB)Total raw data generated/eventData flow rate @ 40kHz L1 (MB/s)Total L2 cpu power @ 40 kHz L1 (SI95)Total L3 cpu power @ 5 kHz L2 (SI95)


Calibration.(M Cattaneo)

Calibration data size and cpu timeUnit Cost

(kSFr) VELO ITrack OTrack RICH1RICH2 PRESH ECALHCALMuonL1Trig TotalNo of channelsEvent Size (kB)Calibration cpu time (SI95 secs)Calibration data stored (kB)Total cpu power @ 1 HzCalibration run frequency / dayTotal calibration data produced / year (GB)


Reconstruction (M Cattaneo)

Reconstruction data size and cpu timeUnit Cost

(kSFr) VELO ITrack OTrack RICH1RICH2 PRESH ECALHCALMuonL1Trig TotalRaw data size input (kB) 0 0 0 0 0 0 0 0 0 0 0Initialisation cpu time /event (SI95 secs)Algorithm cpu time / event (SI95 secs)ESD size output (kB)Event Tag data output (kB)Total cpu power @ n HzTotal ESD data produced / year (GB)Total tag data produced / year (MB)


Group Analysis (G Corti et al)

Group Analysis data size and cpu timeUnit Cost

(kSFr) B>pp B>JY Grp 3 Grp 4 Grp 5 Grp 6 Grp 7 Grp 8 Grp 9 Grp 10 Total

ESD data size input (kB)Event Tag data input (kB)Initialisation cpu time /event (SI95 secs)Algorithm cpu time / event (SI95 secs)AOD size output (kB)Analysis Tag data output (kB)Total cpu power @ n HzTotal AOD data produced / year (GB)Total analysis tag data produced / year (MB)


Physicist Analysis(G Corti et al)

Physicist Analysis data size and cpu time

Unit Cost (kSFr) B>pp B>JY Grp 3 Grp 4 Grp 5 Grp 6 Grp 7 Grp 8 Grp 9 Grp 10 Total

AOD data size input (kB) 0 0 0 0 0 0 0 0 0 0 0Raw data size input (kB)Calibration data size input (kB)Analysis tag data size input (kB)Event Tag data input (kB)Initialisation cpu time /event (SI95 secs)Algorithm cpu time / event (SI95 secs)ntuple size output (kB)Total number of physicists


Urgent Jobs for Country representatives(please treat as a priority activity)

• Read GRID proposal and discuss with country colleagues (where relevant contact country person signing e.g. France,Italy,CERN,Spain,NIKHEF,UK)

• Find out in general what planning is going on in country for providing LHC computing facilities

• Find out what current situation is for HEP computing in LHCb institutes and country– e.g. CPU,Storage, networking,s/w environment

• Liaise with WG on general LHCb model and how their institutes fit in to distribution of resources. Also physics analysis inputs will be very welcome!


Computing Model joblist (our presentation will be in period Mar 22-24)

• Agree on logical dataflow model…complete soon. (John,Frank, Gloria et al) Mar 1

• Agree structure of corresponding spreadsheets ( inputs from all please) Feb 29

• Collect numbers and complete the tables (provide Basic Requirements) Mar 6

• Document additional use cases for simulation, calibration, reconstruction, re-reconstruction, analysis

– input Marco, Gloria, Florence, …. Mar 10

(Frank, John,Themis+ Country reps)

• Using MONARC template, identify LHCb’s distribution of centres Mar 1

• Describe how these resources are used today (simulation and testbeam) Mar 10

• Produce a baseline model for how this will evolve for real data by 2005 Mar 10

• Determine what data storage, communications and CPU resources will be needed in centres Mar 10

• Describe plans for use of test beds and MDC’s to validate model and provide intermediate services between now and 2005. (? Who …) ??


How will we work ?(exchange of information etc.)

• WWW site under construction- details on Feb 28.. Will put all working docs

+ links to MONARC,GRID etc… (http://lhcb.cern.ch/computing/hoff-grid)

• For those at CERN lots of working coffees

• For those not at CERN will use WWW, Email (?maybe one video/phone conf) + hard chasing!


Overview of EU GRID proposal• http://nicewww.cern.ch/~les/grid/welcome.html GRID home page

• http://nicewww.cern.ch/~les/grid/reports.htm Draft proposal

• ‘Outline of a proposal for a Data-intensive Computational GRID Testbed’

K Bos(NIKHEF),F Etienne(IN2P3),E Fernandez(IFAE,Spain),F Gagliardi,H Hoffmann,L Robertson(CERN),F Ruggieri,M Mazzucato(INFN),G Vesztergombi(Hungary),R Middleton(RAL,UK)

• Aiming for formal submission by May 10

• Hoffmann et al have met with experiments. Result was that– Experiments asked for a response as to their attitude

– Agreed that proposal, if it goes ahead, must have experiments included in management somehow

• Project is to ‘develop and demonstrate an effective wide-area distributed computing fabric’. Needs resources - people and testbed. Development is essentially s/w(Middleware) and evaluation in testbeds and using GEANT European network

• So please read and find out how it relates to country activities (money, people, planning etc…)

Documents

Draft Agenda for WG meeting, Friday 25 Feb,1400,160-1-009