[ http://issues.apache.org/jira/browse/HADOOP-312?page=comments#action_12430122 ] Doug Cutting commented on HADOOP-312: -------------------------------------
> I thought that I could save the overhead of destroying/creating threads [ ...] Threads should be cheap to create, but keeping too many around can be expensive. Again, I think the life of the thread should be the same as the life of the connection. > I wanted to avoid so-many-unnecessary method invocations when caching is > disabled. Method invocations that check a flag are plenty fast. This is not an inner loop. I'd rather have this code be easier to maintain than a few nanoseconds faster. > 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
