HiveServer does seem to support multiple connections but I think it still has thread-safety problems (https://issues.apache.org/jira/browse/HIVE-80).
We've (www.forward.co.uk) certainly had instability problems with the thrift server in the past and now run 5 or so instances behind the HAProxy load-balancer (http://haproxy.1wt.eu/). Since we did that it's been significantly better. I think the JDBC server still operates using thrift to connect to the HiveServer so I would expect it to have similar problems (but I may have got that wrong :) On 3 May 2011, at 18:59, Matthew Rathbone wrote: > Even if it is single threaded it certainly seems to support multiple > connections. > > We run 5 workers all connected at the same time executing a different query > each ( with a different connection per worker). > > Hope that helps > > Matthew > On Tuesday, May 3, 2011 at 1:40 PM, V.Senthil Kumar wrote: > Thanks Matthew. The wiki page http://wiki.apache.org/hadoop/Hive/HiveServer > says >> its single threaded. I have a queue of queries which gets added dynamically >> all >> the time. By the time I run 1 query using 1 JDBC connection, the queue gets >> added more queries and builds up a backlog. So, I was that's why I was >> wondering >> whether I can run two or more instances to avoid having a big backlog in >> queue. >> >> >> >> ----- Original Message ---- >> From: Matthew Rathbone <matt...@foursquare.com> >> To: user@hive.apache.org >> Sent: Tue, May 3, 2011 7:46:49 AM >> Subject: Re: HIVE Server multiple instances >> >> Why would you want to run two? I think it is multithreaded, so you can query >> it >> from two different connections >> >> -- >> Matthew Rathbone >> Foursquare | Software Engineer | Server Engineering Team >> matt...@foursquare.com | @rathboma | 4sq >> >> On Monday, May 2, 2011 at 6:41 PM, V.Senthil Kumar wrote: >> Hello, >>> >>> I have one instance of HIVE JDBC server running on port 10000. Can I run >>> another >>> >>> instance on different port ? Would it cause a concurrency issue on the >>> underlying data warehouse files ? Please clarify. >>> >>> Thanks, >>> V.Senthil Kumar >> >
