[ 
https://issues.apache.org/jira/browse/HDFS-7523?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14265150#comment-14265150
 ] 

Daryn Sharp commented on HDFS-7523:
-----------------------------------

This patch isn't having any effect because changing the buffer size after 
connecting is a no-op.  The receive buffer size at connect is used in the 
initial tcp window calculation that is advertised to the server.  If you do set 
the receive buffer prior to connect, then you typically disable auto-tuning in 
your TCP stack which may actually be detrimental to performance.

> Setting a socket receive buffer size in DFSClient
> -------------------------------------------------
>
>                 Key: HDFS-7523
>                 URL: https://issues.apache.org/jira/browse/HDFS-7523
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: dfsclient
>    Affects Versions: 2.6.0
>            Reporter: Liang Xie
>            Assignee: Liang Xie
>         Attachments: HDFS-7523-001 (1).txt, HDFS-7523-001 (1).txt, 
> HDFS-7523-001.txt, HDFS-7523-001.txt, HDFS-7523-001.txt
>
>
> It would be nice if we have a socket receive buffer size while creating 
> socket from client(HBase) view, in old version it should be in 
> DFSInputStream, in trunk it seems should be at:
> {code}
>   @Override // RemotePeerFactory
>   public Peer newConnectedPeer(InetSocketAddress addr,
>       Token<BlockTokenIdentifier> blockToken, DatanodeID datanodeId)
>       throws IOException {
>     Peer peer = null;
>     boolean success = false;
>     Socket sock = null;
>     try {
>       sock = socketFactory.createSocket();
>       NetUtils.connect(sock, addr,
>         getRandomLocalInterfaceAddr(),
>         dfsClientConf.socketTimeout);
>       peer = TcpPeerServer.peerFromSocketAndKey(saslClient, sock, this,
>           blockToken, datanodeId);
>       peer.setReadTimeout(dfsClientConf.socketTimeout);
> {code}
> e.g: sock.setReceiveBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE);
> the default socket buffer size in Linux+JDK7 seems is 8k if i am not wrong, 
> this value sometimes is small for HBase 64k block reading in a 10G network(at 
> least, more system call)



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to