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Date: Mon, 13 Oct 2014 11:48:29 -0700
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On 9/11/2014 12:23 AM, Ben Morrow wrote:
> Is there any way (short of building a new pool) to get a reasonable idea
> of how much extra space a given pool would use if converted?

Take the average file size modulo 4096, round it up to a multiple of 
512, subtract that from 4096, then multiply by the number of files in 
the data set.