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Performance Analysis of the Optical Link. The Storage Resource Manager (SRM). Detailed performance analysis of the CERN-RAL link was carried out using UDPmon (http://www.hep.man.ac.uk/u/rich/net/) . Tests ensured that no significant packet loss was occurring.
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Performance Analysis of the Optical Link The Storage Resource Manager (SRM) Detailed performance analysis of the CERN-RAL link was carried out using UDPmon (http://www.hep.man.ac.uk/u/rich/net/). Tests ensured that no significant packet loss was occurring. dCache provides a massive parallel gridftp service to over 120TB of storage.This provides an SRM front end and HSM capability to a Storage Tape Robot. Local tests show that the base configuration (4 disk servers) is capable of almost 4Gb/s I/O rate. (http://www.dcache.org/) The UK Particle Physics Tier1 Service High Performance Data Transfer for the LHC Service Challenges The LHC Service Challenge Timeline and Milestones LHC Service Challenge • The LCG Service Challenges are aimed at helping to achieve the goal of a production quality world-wide Grid that meets the requirements of the LHC experiments in terms of functionality and scale. • The programme currently involves both the 4 LHC experiments as well as the Tier0, all Tier1s and a number of key Tier2s, allowing all primary data flows to be demonstrated. • On the last service challenge: • We managed to obtain close to 1GB/s for extended periods • Several sites exceeded the targets agreed. • Several sites reached or even exceeded their ‘nominal rates’. • Still see quite a few operational problems. • And the software is not completely debugged yet. • Our main aims now are to: • Get data rates at all Tier1s up to MoU Values. • (Re-)deploy Required Services at Sites so that they meet MoU Targets. • Understand other key Use Cases for verification / validation. • Focus is on service and stability. By September 2006, Tier-1 Centres such as the GRIDPP Tier-1 Centre at RAL must develop and put in place infrastructures to cope with sustained data rates of 400MB/s from CERN. In order to meet this challenge, a number of “Service Challenges” are planned between now and the start of LHC data taking in 2007 (https://uimon.cern.ch/twiki/bin/view/LCG/LCGServiceChallenges) The UK’s prototype optical private network (OPN) to CERN The prototype OPN service has been provided by the UKLIGHT project managed by UKERNA. Four dedicated 1Gb/s links have been provisioned between RAL and CERN. This is planned to be replaced by a dedicated 10Gb link over SuperJanet 5 in the second half of the year.(http://www.uklight.ac.uk/). The LCG 3D project Globally replicated, low volume (tens of terabytes) relational databases will compliment the streamed physics data. (http://lcg3d.cern.ch/) Throughput monitoring by RGMA Sustained data rates of over 170MB/s have been achieved between CERN and RAL.The LCG project uses R-GMA (http://www.r-gma.org/) to capture this data from global producers such as the RAL Tier-1 for presentation in near to real time monitoring pages available on the LCG Service Challenge website.