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Date: Sun, 26 May 2013 18:20:24 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: Adam Vande More <amvandemore@gmail.com>
Subject: Re: "swap" partition leads to instability?
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On Sun, 26 May 2013, Adam Vande More wrote:

> On Sun, May 26, 2013 at 6:32 PM, Warren Block <wblock@wonkity.com> wrote:
>
>> Another problem with SSDs is that they can have difficulty with wear
>> leveling.  This is even worse with swap because there is no way to use TRIM
>> to tell the SSD about blocks that have been freed.
>
> Um, that is wrong.

Which part?  A FreeBSD swap partition has no way to use TRIM, so I 
suggest using a swap file on top of UFS, which does support TRIM.

> It is in fact the basically the point of TRIM.
> And SSD's typically use the best form of wear leveling and it's
> usually advisable to leave a bit of the drive unpartitioned/unused to
> ensure the wear leveling works optimally.

Using TRIM should preserve performance better than leaving unused space 
and letting the drive wear leveling algorithm move data around without 
the hint.