US-CMS T2 Centers US-CMS Tier 2 Report Patricia McBride Fermilab GDB Meeting August 31, 2007 Triumf - Vancouver

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers2 US Tier 2s for CMS There are 7 CMS Tier- 2 centers in the US. The US-Tier 2s are hosted at universities and are OSG sites. Funding through the US-CMS Software and Computing Project. L2 coordinator for US- CMS T2s: Ken Bloom, U. of Nebraska

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers3 Current US CMS T2 Resources US CMS T2 Site CPU (kSI2K) Disk (TB)WAN (Gb/s) Caltech Florida MIT Nebraska Purdue UCSD Wisconsin

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers4 US-CMS Tier2s In 2008 we expect all US T2 sites to be operating with 1M SI2K of CPU, 200TB disk and 10Gbit/s WAN - nearly double the current resource levels. Note: In CMS about half the T2 resources are dedicated to simulation and the other half to analysis activities. Some details All US T2 sites use SL4 with Condor (or PBS), Disk pools are managed by dCache with SRM as an interface for remote data transfers. Gratia provides the accounting services. CMSSW software and CMS services such as PheDEX are installed at the sites.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers5 US -Tier 2 coordination and operations T2 sites are operated by the university groups. –Close connection to the CMS local user community –Local management of the facilities, purchases –Coordination through US CMS S&C project Each T2 site has 2 FTEs for operations: –This includes 1 FTE for operations of the storage system. Good communication and planning has paid off –The T2’s have a close collaboration with Fermilab and the FNAL T1 group. –There is a US T2 meeting every 2 weeks. –There seems to be good coordination among the sites. T2s provide help for US-Tier3 sites, other OSG sites (Brazil, for example). The sites have often done early deployment and been testers for upgrades to software and services for CMS and OSG.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers6 US-CMS T2 in CSA06 US-CMS T2 sites were leaders during CSA06 in number of jobs hosted. Note the high success rates for these jobs.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers7 Monte Carlo production for CSA07 text US Tier 2 sites are making a major contribution to CMS MC event production: 66M/196M events in the recent months. Expectation for 2007: 50M events per month at all T2 sites. This has been achieved.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers8 Commissioning CMS Computing Model calls for analysis dataset transfers from Tier-1 to non-regional Tier-2s. –The CMS commissioning team has set up a program of work to debug these links and bring them to production quality. Metric for a commissioned T1 T2 link: 4 out of 5 days above 300 GB/day; in excess of 1.7TB for 5 days. Links will be “decommissioned” or removed from production after 7 days with <300 GB/day. Only commissioned links will be used in production for CSA07. –This is a work in progress and it has been vacation season. Stay tuned. The seven US-CMS Tier 2 sites are commissioned and are used in production. –All US-Tier-2 links for transfers to/from the FNAL-Tier-1 have been commissioned. –These sites were used extensively in CSA06 and in pre-CSA07 MC production.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers9 CMS Site Availability Testing Hourly monitoring of sites with CMS SAM tests has improved site availability for CMS. CMS SAM “Green” correlates to high job success rate at site. US T2 sites normally have good availability rankings >80%. 80% Includes OSG/CMS sites in Brazil

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers10 Data Transfers to US-CMS T2 Centers Snapshot of daily transfers

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers11 Data Transfers rates to T2s Average daily transfer rate to US T2s sites is ~80 MB/sec. These rates are dominated by transfers from Fermilab Target: MB/s depending on the link

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers12 Transfers: Source to all US-Tier2 Most transfers to US T2 sites are from FNAL, but CMS has started to commission links to the T2 sites from other (non-regional) T1 sites. All transfers to US T2 Source: Non-regional T1s

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers13 User analysis at the Tier-2s The number of jobs hosted at the seven US CMS T2s is routinely more than 1k/day. We expect the number of jobs to increase during CSA07 when more MC data sets will be hosted at T2 sites for the analysis. (Users needed!)

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers14 Data hosting/data managers Each T2 site will have a data manager who decides which datasets are hosted at the site. –Users make requests which are honored if space is available. T2 disk is regarded as cache; datasets will not reside permanently at a T2. The T2 system is designed for frequent replacement of data sets determined by the needs of the local users or the physics groups. Data managers at US Tier 2 sites. Coordinating the placement of skim datasets at the US-T2 will be tested in CSA07.

US-CMS T2 Centers August 31, 2007US-CMS T2 Centers15 Summary The US Tier 2 sites for CMS have been working well. In early 2008, we expect all sites to be operating at the full capacity required for startup. For more details on US CMS T2 computing, see the CHEP poster by Kenneth Bloom “US CMS Tier-2 Computing”. US-Tier 2s facilities are well organized and there are communication paths between sites to the Tier-1 at Fermilab. –We followed this example and created a new position in the CMS computing org: the T2 liaison. Ken Bloom and Giuseppe Bagliesi are now the liaisons to the T2 sites around the globe.