[ https://issues.apache.org/jira/browse/HADOOP-9150?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13546418#comment-13546418 ]
Todd Lipcon commented on HADOOP-9150: ------------------------------------- bq. Did you mean to make viewfs mount tables case-insensitive? I guess not -- but I did mean to make the HA logical name case-insensitive, since it shows up like a hostname to users. Do you think making viewfs's top level case-insensitive would be a feature or a bug? :) > Unnecessary DNS resolution attempts for logical URIs > ---------------------------------------------------- > > Key: HADOOP-9150 > URL: https://issues.apache.org/jira/browse/HADOOP-9150 > Project: Hadoop Common > Issue Type: Bug > Components: fs/s3, ha, performance, viewfs > Affects Versions: 3.0.0, 2.0.2-alpha > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Critical > Attachments: hadoop-9150.txt, hadoop-9150.txt, log.txt, > tracing-resolver.tgz > > > In the FileSystem code, we accidentally try to DNS-resolve the logical name > before it is converted to an actual domain name. In some DNS setups, this can > cause a big slowdown - eg in one misconfigured cluster we saw a 2-3x drop in > terasort throughput, since every task wasted a lot of time waiting for slow > "not found" responses from DNS. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira