[ http://issues.apache.org/jira/browse/HADOOP-312?page=comments#action_12430568 ] Sameer Paranjpye commented on HADOOP-312: -----------------------------------------
> There are not many threads in the system. Perhaps, but thread creation is quite cheap. I see two reasons for not keeping threads around. a) The code will be simpler if all objects associated with a server (connection and thread in this case) are created/destroyed together. b) The point of not caching connections is to avoid lingering unused resources, that applies to threads as much as it does to connections. If there is a use case where connections are created/destroyed once/second/server then the appropriate course to avoid this thrash would be to enable connection caching, no? > Connections should not be cached > -------------------------------- > > Key: HADOOP-312 > URL: http://issues.apache.org/jira/browse/HADOOP-312 > Project: Hadoop > Issue Type: Improvement > Components: ipc > Reporter: Devaraj Das > Assigned To: Devaraj Das > Attachments: no_conn_caching.patch, no_conn_caching.patch, > no_conn_caching.patch, no_connection_caching.patch, > no_connection_caching.patch > > > Servers and clients (client include datanodes, tasktrackers, DFSClients & > tasks) should not cache connections or maybe cache them for very short > periods of time. Clients should set up & tear down connections to the servers > everytime they need to contact the servers (including the heartbeats). If > connection is cached, then reuse the existing connection for a few subsequent > transactions until the connection expires. The heartbeat interval should be > more so that many more clients (order of tens of thousands) can be > accomodated within 1 heartbeat interval. -- 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
