Service Challenge Phase 4:

1

• Service Challenge Phase 4
• Piano di attività e impatto sulla infrastruttura
  di rete
• Tiziana Ferrari
• INFN CNAF
• CCR, Roma, 20-21 Ottobre 2005

2
Service Challenge 3

• Now in SC3 Service Phase (Sep Dec 2005)
• ALICE, CMS and LHCb have all started their
  production
• ATLAS are preparing for November 1st start
• Service Challenge 4 May 2006, Sep 2006

3
SC3 INFN Sites (1/2)

• CNAF
• LCG File Catalogue (LFC)
• File Transport Service (FTS)
• Myproxy server and BDII
• Storage
• CASTOR with SRM interface
• Interim installations of sw components from some
  of the experiments (not currently available from
  LCG) - VObox

4
SC3 INFN sites (2/2)

• Torino (ALICE)
• FTS, LFC, dCache (LCG 2.6.0)
• Storage Space 2 TBy
• Milano (ATLAS)
• FTS, LFC, DPM 1.3.7
• Storage space 5.29 TBy
• Pisa (ATLAS/CMS)
• FTS, PhEDEx, POOL file cat, PubDB, LFC, DPM 1.3.5
• Storage space 5 TBy available, 5 TBy expected
• Legnaro (CMS)
• FTS, PhEDEx, Pool file cat., PubDB, DPM 1.3.7 (1
  pool, 80 Gby)
• Storage space 4 TBy
• Bari (ATLAS/CMS)
• FTS, PhEDEx, POOL file cat., PubDB, LFC, dCache,
  DPM
• Storage space 5 TBy available
• LHCb
• CNAF

5
INFN Tier-1 SC4 short-term plans (1/2)

• SC4 storage and computing resources will be
  shared with production
• Storage
• Oct 2005 Data disk
• 50 TB (Castor front-end)
• WAN?Disk performance 125 MB/s (demonstrated,
  SC3)
• Oct 2005 Tape
• 200 TB (4 9940B 6 LTO2 drives)
• Drives shared with production
• WAN?Tape performance mean sustained 50 MB/s
  (SC3, throughput phase, July 2005)
• Computing
• Oct 2005 min 1200 kSI2K, max1550 kSI2K (as the
  farm is shared)

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INFN Tier-1 SC4 short-term plans (2/2)

• Network
• Oct 2005
• 2 x 1 GEthernet links CNAF ?? GARR, dedicated to
  SC traffic to/from CERN
• Future
• ongoing upgrade to 10 GEthernet, CNAF ? ? GARR,
  dedicated to SC
• Usage of policy routing at the GARR access point
• Type of connectivity to INFN Tier-2 under
  discussion
• Backup link Tier-1 ? ?Tier-1 (Karlsruhe) under
  discussion
• Software
• Oct 2005
• SRM/Castor and FTS
• farm middleware LCG 2.6
• Future
• dCache and StoRM under evaluation (for disk-only
  SRMs)
• Possibility to upgrade to CASTOR v2 under
  evaluation (end of year 2005)

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What target rates for Tier-2s?

• LHC Computing Grid Technical Design Report
• Access link at 1 Gb/s by the time LHC starts
• Traffic 1 Tier-1 ? ? 1 Tier-2 10 Traffic
  Tier-0 ? ? Tier-1
• Estimations of traffic Tier-1 ? ? Tier-2
  represent an upper limit
• Tier-2 ? ? Tier-2 replications will lower loan on
  the Tier-1

WSF with safety factor
8
TDR bandwidth estimation

• LHC Computing Grid Technical Design Report
  (giugno 2005)http//lcg.web.cern.ch/LCG/tdr/

9
Expected rates (rough / with_safety-factor)
10
Necessita vs specifiche Tier-2
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The Worldwide LHC Computing GridLevel 1 Service
Milestones

• 31 Dec 05
• Tier-0/1 high-performance network operational at
  CERN and 3 Tier-1s.
• 31 Dec 05
• 750 MB/s data recording demonstration at CERN
  Data generator disk tape sustaining 750 MB/s for
  one week using the CASTOR 2 mass storage system.
• Jan 06 Feb 06
• Throughput tests
• SC4a 28 Feb 06
• All required software for baseline services
  deployed and operational at all Tier-1s and at
  least 20 Tier-2 sites
• Mar 06
• Tier-0/1 high-performance network operational at
  CERN and 6 Tier-1s, at least 3 via GEANT.
• SC4b 30 Apr 06
• Service Challenge 4 Set-up Set-up complete and
  basic service demonstrated, capable of running
  experiment-supplied packaged test jobs, data
  distribution tested.
• 30 Apr 06
• 1.0 GB/s data recording demonstration at CERN
  Data generator disk tape sustaining 1.0 GB/s for
  one week using the CASTOR 2 mass storage system
  and the new tape equipment.
• SC4 31 May 06 Service Challenge 4
• Start of stable service phase, including all
  Tier-1s and 40 Tier-2 sites.

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The Worldwide LHC Computing GridLevel 1 Service
Milestones

• The service must be able to support the full
  computing model of each experiment, including
  simulation and end-user batch analysis at Tier-2
  sites.
• Criteria for successful completion of SC4 By end
  of service phase (end September 2006)
• 8 Tier-1s and 20 Tier-2s must have demonstrated
  availability better than 90 of the levels
  specified the WLCG MoU adjusted for sites that
  do not provide a 24 hour service
• Success rate of standard application test jobs
  greater than 90 (excluding failures due to the
  applications environment and non-availability of
  sites)
• Performance and throughput tests complete
  Performance goal for each Tier-1 is
• the nominal data rate that the centre must
  sustain during LHC operation (200 MB/s for CNAF)
  
• CERN-disk ? network ? Tier-1-tape.
• Throughput test goal is to maintain for one week
  an average throughput of 1.6 GB/s from disk at
  CERN to tape at the Tier-1 sites. All Tier-1
  sites must participate.
• 30 Sept 06
• 1.6 GB/s data recording demonstration at CERN
  Data generator??? disk ? tape sustaining 1.6 GB/s
  for one week using the CASTOR mass storage
  system.
• 30 Sept 06
• Initial LHC Service in operation Capable of
  handling the full nominal data rate between CERN
  and Tier-1s. The service will be used for
  extended testing of the computing systems of the
  four experiments, for simulation and for
  processing of cosmic-ray data. During the
  following six months each site will build up to
  the full throughput needed for LHC operation,
  which is twice the nominal data rate.
• 24 hour operational coverage is required at all
  Tier-1 centres from January 2007

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Milestones in brief

• Jan 2006
• throughput tests (rate targets not specified)
• May 2006
• high-speed network infrastructure operational
• By Sep 2006
• avg throughput of 1.6 GB/s from disk at CERN to
  tape at the Tier-1 sites (nominal rate for LHC
  operation, 200 MB/s for CNAF)
• Oct 2006 Mar 2007
• avg throughput up to twice the nominal rate

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Target (nominal) data rates for Tier-1 sites and
CERN in SC4