Atlas:SC4

Bienvenue sur la page Atlas SC4 LCG-France

Welcome to the LCG-France Atlas SC4 page

Twiki page : SC4 ATLAS

Compte rendu de la réunion SC4 ATLAS au CERN du 9 Juin (S.Jézéquel, G. Rahal) (written in french)

• T0 Role(CERN)
  • Produce dummy files with 1 to 2 GB size(RAW, ESD et AOD) (see T0 Twiki)
  • Initiate T0->T1 transfers
  • FTS server sents files to Lyon choosing between 'TAPE' (RAW 43,2 Mo/s) or 'DISK' (ESD,AOD 23+20 Mo/s) areas
• T1 Role (CCIN2P3)
  • Get files from T0 (dedicated dcache area: L. Schwarz)
  • Provides LFC (lfc-atlas.in2p3.fr) and FTS service (cclcgftsli01.in2p3.fr) (D. Bouvet)
  • Send all AODs to each T2 (20 Mo/s) using Lyon FTS server
  • Regurlarly cleanup files
• T2 Role (BEIJING, LAL, LAPP, LPC, LPNHE, SACLAY, TOKYO)
  • Get files from T1 (Lyon). Files on the T2 are written in /home/atlas/sc4tier0/...
  • Clean-up the files (?)
• Other roles
  • ATLAS (S. Jézéquel, G. Rahal) : Initiate T1->T2 transfers

Information from DDM monitoring

• Main DDM monitoring page

• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stack4h.png http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stack4ht2.png

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• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackday.png
• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackdayLYON.png
• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackdayt2.png

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• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackweek.png
• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackweekLYON.png
• http://atlas-ddm-monitoring.web.cern.ch/atlas-ddm-monitoring/rrd/plots/stackweekt2.png

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• Transfer rates for LYON and associated T2s (validated files by DDM):
  • LYON
  • BEIJING
  • LAL
  • LAPP
  • LPC
  • LPNHE
  • SACLAY
  • TOKYO

• Detailed information on each site

• File transfer state in LYON

Information from FTS monitoring

• Atlas FTS transfer rate

• CERN->Lyon FTS transfer rate

• T1->T2 :
  • 15 concurrent files and 10 streams for LYON-TOKYO
  • 5 concurrent files and 5 streams for LYON-BEIJING (SE not enough powerful for 15/15 )
  • 10 concurrent files and 10 streams for LYON-French T2s (LAL, LPNHE, LPC, SACLAY) except for LAPP (5 concurrent files and 1 stream)

Information from dCache monitoring (provided by Lyon)

• Monitoring of dcache for SC4 areas
• LYONDISK : 25 gridftp concurrent access maximum
• LYONTAPE : 10 gridft concurrent access maximum

VOBOX Configuration

• 4 processors 3 GHz
• 4 GB of memory ( 2 GB dedicated to SWAP)
• The monitoring of the Vobox daily, weekly and monthly can be found Here

Disk space availability

• BEIJING
• CPPM
• GRIF
• LPC
• LAPP
• TOKYO
• LYON

Daily news

• SC4 Data Managment Daily log

• 20 June 2006: Mail from Miguel Branco (DDM responsible)

Today we started deploying DQ2 on the remaining T1 sites (not all sites still available).
Attached is the result of a (nice) ramp up, easily beating SC3's record (on the 1st day of export of SC4) peaking at ~ 270 MB/s. Each 'step' in the graph is an additional T1 being added to the export.
Dataset subscriptions are now slowing down and will resume tomorrow. Our DQ2 monitoring has been turned off and we expect to have it back tomorrow! Still a long way to go until we have a reasonable understanding of the limiting factors..

• SC4 transfers from LYON to T2s:
  • Simultaneous transfers to the 7 T2 sites for more than 24 hours; it reached more than 25MB/s
  • 

Post-mortem DDM meeting

• Presentation at CERN (M. Branco) showing the results of the SC4 tests. (1 August 2006)