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Date: Thu, 28 Aug 2014 17:24:04 -0500
Message-ID: <CA+tpaK0UpDCvBuMpnOkDXNfcnkuBfB-6tv2cMuyRjah5Z3xPRQ@mail.gmail.com>
Subject: Re: TRIM considerations when repartitioning a SSD
From: Adam Vande More <amvandemore@gmail.com>
To: Mike Clarke <jmc-freebsd2@milibyte.co.uk>
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On Thu, Aug 28, 2014 at 4:54 PM, Mike Clarke <jmc-freebsd2@milibyte.co.uk>
wrote:

>
> FreeBSD 9.3-RELEASE
>
> I may soon need to repartition a SSD which has a zpool on it and was
> wondering what is the best method of ensuring that all blocks get
> marked as no longer in use.
>
> Is gpart sufficiently TRIM aware to be able to just use gpart delete?


Extremely doubtful that it is.  You generally must reset the drive eg

camcontrol security da4 -s buhbyesweetdata -e buhbyesweetdata


-- 
Adam