[ https://issues.apache.org/jira/browse/HDFS-2982?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13280613#comment-13280613 ]
Todd Lipcon commented on HDFS-2982: ----------------------------------- Oops, missed part of my copy-paste comment: {code} + LOG.info(this + ": selecting input streams starting at " + fromTxId + + (inProgressOk ? " (inProgress ok) " : " (excluding inProgress) ") + + "from among " + elfs.size() + " candidate file(s)"); {code} This should probably be DEBUG level. Otherwise this will show up in the "safety check" selectInputStreams call, and potentially confuse users. > Startup performance suffers when there are many edit log segments > ----------------------------------------------------------------- > > Key: HDFS-2982 > URL: https://issues.apache.org/jira/browse/HDFS-2982 > Project: Hadoop HDFS > Issue Type: Bug > Components: name-node > Affects Versions: 2.0.0 > Reporter: Todd Lipcon > Assignee: Colin Patrick McCabe > Priority: Critical > Attachments: HDFS-2982.001.patch, HDFS-2982.002.patch, > HDFS-2982.003.patch, HDFS-2982.004.patch, HDFS-2982.005.patch, > HDFS-2982.006.patch, HDFS-2982.007.patch, HDFS-2982.008.patch > > > For every one of the edit log segments, it seems like we are calling > listFiles on the edit log directory inside of {{findMaxTransaction}}. This is > killing performance, especially when there are many log segments and the > directory is stored on NFS. It is taking several minutes to start up the NN > when there are several thousand log segments present. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira