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Todd Lipcon commented on HDFS-2243: ----------------------------------- Hi Eric. HDFS-918 addresses part of this problem. HDFS-941 also addresses it substantially for the HBase workload. > DataXceiver per accept seems to be a bottleneck in HBase/YCSB test > ------------------------------------------------------------------ > > Key: HDFS-2243 > URL: https://issues.apache.org/jira/browse/HDFS-2243 > Project: Hadoop HDFS > Issue Type: Bug > Components: data-node > Affects Versions: 0.23.0 > Environment: Using Fedora 14 on a quad core phenom system > Reporter: Eric Caspole > Priority: Minor > > I am running the YCSB benchmark against HBase, sometimes against a single > node, sometimes against a cluster of 6 systems. As the load increases into > thousands of TPS, especially on the single node, I can see that the datanode > runs very high system time and seems to be bottlenecked by how fast it can > create the threads to handle the new connections in DataXceiverServer.run. By > "perf top" I can see the process spends about 12% of all its time in > pthread_create, and in hprof profiles I can see there are tens of thousands > of threads created in just a few minutes of test execution. > Does anyone else observe this bottleneck? Is there a major challenge to using > a thread pool of DataXceivers in this situation? -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira