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Date: Fri, 22 Aug 2014 17:34:52 +0100
From: Arthur Chance <freebsd@qeng-ho.org>
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To: RW <rwmaillists@googlemail.com>, freebsd-questions@freebsd.org
Subject: Re: solid state drives?
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On 22/08/2014 17:01, RW wrote:
> On Mon, 18 Aug 2014 12:36:29 -0500
> William A. Mahaffey III wrote:
>
>
>> None of the SSD's are/will be as durable as spinning drives for
>> writes .... That said, the SLC type are more durable than MLC or
>> TLC .... Also more $$$$ & usually only available in smaller sizes.
>> Good for a root drive, i.e. mostly read-olny operations. Swap &
>> everything else on spinning platters ....
>
> A typical modern 120GB MLC SSD will have a specified write endurance of
> around 8TB which is equivalent to  1GB a day for 22 years. They should
> be fine for most things where there's nothing doing heavy duty writing.

The stated write endurances appear to be very conservative as well. The 
Tech Report web site has been hammering a variety of SSDs and only 
started getting actual failures after the 600TB mark, with some still 
working after 1PB of writes.

http://techreport.com/review/26523/the-ssd-endurance-experiment-casualties-on-the-way-to-a-petabyte

YMMV of course.