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From Prasad Chakka <>
Subject Re: thread cofinement session state
Date Tue, 10 Mar 2009 03:23:05 GMT
I am assuming he is using the same code as MetaStore server. AFAIK, TThreadPoolServer is supposed
to use a new thread for each connection.

From: Joydeep Sen Sarma <>
Reply-To: <>
Date: Mon, 9 Mar 2009 20:16:22 -0700
To: <>
Subject: RE: thread cofinement session state

(also been reading up on this code a bit just now)

That's weird. It seems to be using TThreadPoolServer and that seems to just service all requests
from a single connection in one thread. (and uses the same processor I assume that seems to
initialize the session state in the interface constructor)

Are ur execute calls happening on the same connection?


From: Min Zhou []
Sent: Monday, March 09, 2009 8:03 PM
Subject: thread cofinement session state

Hi list,
   I found each invoke of HiveServer's execute method run in different threads. Those threads
which execute a HSQL query(not a client connection may execute several pieces of queries),
have not their own session state. when I call SessionState.get(), it will return null beacuse
session state on this thread hadnot been constructed before. see also fragment of

  public static String getRealFiles(Configuration conf) {
    // fill in local files to be added to the task environment
    SessionState ss = SessionState.get();  // return ss will get null !!!

Is it a bug?

My research interests are distributed systems, parallel computing and bytecode based virtual

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