I am running the XRootD 3.0.5 release from the yum repo and am seeing rather severe performance issues. I have a system of 12 active batch machines with a total of just over 200 batch slots. When the batch system is full of jobs -- and this happens with a number of different types of jobs -- I see very poor performance from the xrootd server. I see load averages of 140 to 200 or more and I see a high percent of CPU time in wait states (70-80%) with a large number of interrupts (10-15K), both of these reported by dstat. The server is a Dell R710 with MD1000 disk arrays attached with SAS interconnects. There is a 10G network interface and I have measured over 800 Gb/s total network throughput using xrdcp simultaneously on 10 machines. There are two namespaces, managed by two xrootd servers. When the main namespace gets clogged up by batch jobs, the second namespace still performs well. Is it expected that an xrootd process would not be able to handle 200 simultaneous data flows? If not, how should I go about debugging this system? Thanks. Paul T. Keener Department of Physics and Astronomy University of Pennsylvania