[ http://issues.apache.org/jira/browse/HADOOP-64?page=comments#action_12427595 ] Doug Cutting commented on HADOOP-64: ------------------------------------
Since we only expect to have around 10k blocks per node, storing the table in memory should not be a problem. With even 100k blockids per nodem, at 100bytes of RAM per blockid, a datanode would only require 10MB. So optimizing this seems premature. > DataNode should be capable of managing multiple volumes > ------------------------------------------------------- > > Key: HADOOP-64 > URL: http://issues.apache.org/jira/browse/HADOOP-64 > Project: Hadoop > Issue Type: Improvement > Components: dfs > Affects Versions: 0.2.0 > Reporter: Sameer Paranjpye > Assigned To: Milind Bhandarkar > Priority: Minor > Fix For: 0.6.0 > > > The dfs Datanode can only store data on a single filesystem volume. When a > node runs its disks JBOD this means running a Datanode per disk on the > machine. While the scheme works reasonably well on small clusters, on larger > installations (several 100 nodes) it implies a very large number of Datanodes > with associated management overhead in the Namenode. > The Datanod should be enhanced to be able to handle multiple volumes on a > single machine. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
