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Date: Tue, 02 Sep 2003 23:33:55 +0300
From: Petri Helenius <pete@he.iki.fi>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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cc: Max Clark <max.clark@media.net>
Subject: Re: FW: 20TB Storage System
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Poul-Henning Kamp wrote:

>>2) What is the maximum size of a filesystem that I can present to the host
>>OS using vinum/ccd? Am I limited anywhere that I am not aware of?
>>    
>>
>
>Good question, I'm not sure we currently know the exact barrier.
>
Just make sure you run UFS2, which is the default on -CURRENT because 
UFS1 has
a 1TB limit.

>>3) Could I put all 20TB on one system, or will I need two to sustain the IO
>>required?
>>    
>>
>
>Spreading it will give you more I/O bandwidth.
>
>  
>
Can you say why? Usually putting more spindles into one pile gives you 
more I/O,
unless you have very evenly distributed sequential access in pattern you 
can predict
in advance.

Pete