Speaker
Description
The WLCG Data Challenge series drives change and performance improvements in our data movement systems, required in time for the start of the High-Luminosity LHC (HL-LHC). Following challenges in 2021 and 2024, this talk describes the planning in progress for the challenge in 2027, expected to take place near the start of the year. The four LHC experiments plan to take part, alongside others with data-intensive science using much of the same infrastructure and tools. Each subsequent challenge sets higher rate targets and increased complexity than the last, with the goal for DC27 sitting at 50% of the estimated HL-LHC data rates. Additional goals include scale testing of the new version of FTS (FTS4), performing all transfers using tokens, and performance read/write testing of tape systems. Plans are also in place for an XRootD load-test tool and improved XRootD monitoring to be involved in the challenge.