Re: Any tools/scripts for finding underlying cause of concurrency?

From: Mladen Gogala <>
Date: Sun, 8 Mar 2009 16:44:24 +0000 (UTC)
Message-ID: <gp0sl7$rm2$>

On Sun, 08 Mar 2009 08:56:27 -0700, vm22 wrote:

> We have been having concurrency issues for the past week but have
> managed to resolve it (the underlying cause of it was a bug).

Concurrency issues? Any details?

> One thing
> that I wanted to know is that if there are any tools or scripts out
> there to tell us immediately the cause of the concurrency?

Concurrency is a noun which means that the database is accessed simultaneously by several users. One of the most efficient tools to resolve "concurrency issues" is a baseball bat, applied delicately on top of the user's head.

> All we saw in OEM was a couple of statements which were the Top SQL as
> well as a session that was blocking and several being blocked. We could
> not see the underlying SQL that was causing it. Eventually, the issue
> was the UNDO segments being released from a huge transaction - thereby
> causing the concurrency.

Undo segments, being released and thus causing the concurrency? I believe that all your base are belong to us. You are on the way to destruction.

Received on Sun Mar 08 2009 - 11:44:24 CDT

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