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Date: Thu, 14 Jan 2010 17:16:11 +0100
To: "Eduardo Piombino" <drakorg@gmail.com>, "Craig James"
	<craig_james@emolecules.com>
Subject: Re: a heavy duty operation on an "unused" table kills my
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> "high CPU usage" It might very well be "high IO usage".

	Try this :

	Copy (using explorer, the shell, whatever) a huge file.
	This will create load similar to ALTER TABLE.
	Measure throughput, how much is it ?

	If your server blows up just like it did on ALTER TABLE, you got a IO  
system problem.
	If everything is smooth, you can look into other things.

	How's your fragmentation ? Did the disk ever get full ? What does the  
task manager say (swap in/out, disk queue lengthn etc)

	PS : try a separate tablespace on another disk.