[ https://issues.apache.org/jira/browse/HDFS-3697?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13420793#comment-13420793 ]
Todd Lipcon commented on HDFS-3697: ----------------------------------- You mean the datanode, right? It would be worth considering adding these as per-stream flags - e.g an HDFS "fadvise"-like API on DFSInputStream/DFSOutputStream that changes the behavior. Then, the datanode-wide flags would just serve as defaults. > Enable fadvise readahead by default > ----------------------------------- > > Key: HDFS-3697 > URL: https://issues.apache.org/jira/browse/HDFS-3697 > Project: Hadoop HDFS > Issue Type: Improvement > Components: data-node, performance > Affects Versions: 3.0.0, 2.2.0-alpha > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Minor > Fix For: 3.0.0, 2.2.0-alpha > > Attachments: hdfs-3697-branch-1.txt, hdfs-3697.txt, hdfs-3697.txt > > > The fadvise features have been implemented for some time, and we've enabled > them in production at a lot of customer sites without difficulty. I'd like to > enable the readahead feature by default in future versions so that users get > this benefit without any manual configuration required. > The other fadvise features seem to be more workload-dependent and need > further testing before enabling by default. -- 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