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Date: Mon, 31 Aug 2015 18:11:35 +0100
From: RW <rwmaillists@googlemail.com>
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Subject: Re: Replacing Drive with SSD
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On Mon, 31 Aug 2015 12:52:43 -0400
Quartz wrote:

> >
> > It provides a pool of blocks that have not and will not be
> > written.  
> 
> Bbut how does the drive "know" that those blocks are not allocated by
> a partition somewhere and are safe to use as spares? It's not like
> the drive firmware reads into the partition table or anything.

It's analogous to virtual memory. It's the unused physical blocks that
form the free pool. The point of leaving the unpartitioned space is
that it's a region of a logical address space with no physical blocks
attached.