> > > Also, NameNode provides a URL named "streamFile" which allows any HTTP > client to get the stored files. Any idea how it's operations compare in > terms of speed to client HDFS access?
What happens here is that the NameNode redirects you to a "smartly" (a data node that has some of the file's first 5 blocks, I think) chosen DataNode, and that DataNode proxies the file for you. Specifically, the assembling of a full file from multiple nodes is happening on that DataNode. If you were using a DFSClient, it would assemble the file from blocks at the client, and talk to many data nodes. -- Philip
