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Date: Fri, 30 May 2014 19:10:53 +0200
From: Heinz Diehl <htd@fancy-poultry.org>
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Subject: Re: [dm-crypt] Is erasing hard disk drive mandatory?
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To: dm-crypt@saout.de

On 30.05.2014, Thomas Bastiani wrote: 

> On SSD's though, this would prevent TRIM from functioning properly 
> and make the SSD appear as full to the controller which would 
> hurt performance.

If you e.g. do a "dd if=/dev/urandom of=bigfile" to a SSD drive
until the partition is fully overwritten, simply deleting "bigfile" 
followed by a "fstrim" should restore performance to the same level as
is was before. What am I missing?