[ale] no putting swap on ssd

[Ron Frazier]

Hi all, I decided to reply to several people in one post, and add some 
new info. Thanks to all who replied. Thanks also for the links provided.

Sparr wrote:

I don't expect to still be using measly 128GB drives in ten years :)

(Ron) I've been known to run drives for 5 years. I don't think I have 
any that old right now, but I generally run computers and cars until 
they die or become unbearably slow.

Greg Freemyer wrote:

I think the typical lifetime is 10,000 writes per Erase Block.
<snip>
Note that I wrote that whole wiki page, so if you have questions, feel
<snip>
If 10,000 is right and you follow my original logic, the 400 days of
continuous operation drops to 4 days of continuous operation!

(Ron) 10,000 looks like the right number. It's the one Steve Gibson 
quotes. That one article you posted implies 5000.

JD wrote:

of the following discussion concerned encrypted SSD wear.  I left
thinking that I'd plan for a new SSD every 3 yrs if I put a Windows swap

(Ron) I'm going to post some followup info below. Steve reaffirmed his 
concerns.

Richard Bronosky wrote:

Yeah, my initial thought was that I would not want windows abusing an
SSD. I go over my M-i-L's house and the sound of the 3 windows
computers in that house grinding constantly, regardless of whether or
not anyone is using them, drives me crazy.

(Ron) If you maintain these, you can A) Defrag them. Try this free 
defragger: http://www.auslogics.com/en/software/disk-defrag/ B) Add RAM 
to get at least 4 GB if possible. C) Verify that the swap file is either 
active and system managed and at the recommended size OR manually set to 
2X RAM and actually is that size. This should help reduce disk 
thrashing. Also, disk thrashing can mean pending disk failure. Boot a 
Ubuntu CD and run Disk utility then a long smart test.

Brian Pitts wrote:

If you're interested in but unfamiliar with this topic, I recommend readin

(Ron) That's a cool link you posted.

(Ron) As it turns out, Steve gave further information in his next 
podcast which I hadn't listened to when I wrote my original post. He 
reaffirmed his advice not to put swap on SSD, and assures us he's talked 
to experts who've experimentally proven the problem is real. Here are 
links to a transcript of the podcast, and the podcasts in question.

http://www.grc.com/securitynow.htm - see podcasts 282 and 284

http://media.grc.com/sn/sn-282.mp3 - podcast
http://www.grc.com/sn/sn-282.pdf - transcript

Quote from transcript:

You really can burn them out. I know, for

example, Mark Thompson has done so with CompactFlash drives.

And I will say again, you absolutely want to turn off your swapping. You do not want to

have a swapping file, the virtual memory on that drive. Typically these days I think the

need for virtual memory is diminishing because it's so easy to run two or three gigs of

regular solid-state primary RAM on your machine, I often don't have a swap file on any of

my machines that have physical drives. It's just becoming less necessary, I think. But

you really, it doesn't make sense to have a swap file on an SSD because, even though it

would offload your RAM, then you really are exercising that SSD all the time while the

system is copying RAM in and out of the drive. So that you do want to turn off.

End Quote

http://media.grc.com/sn/sn-284.mp3 - Podcast
http://www.grc.com/sn/sn-284.pdf - Transcript

Quote from transcript:

And Mark Thompson and I have discussed this at length. He's performed the

experiment of using an SSD for a swap file and watching it burn out the SSD. I mean, in

a relatively short time it just killed it. And so, anyway, so my advice stands, which is, if

you're using an SSD, hopefully before you have gone to the expense of using an SSD,

which is still much more expensive than a hard drive, you will have invested money in as

much RAM as your system can handle because RAM is much less expensive, and you'll

get much more, you'll get huge benefit from going to the most RAM you can possible get.

And if you've done that, then turn off pagefiles. And if the only drive you have is an SSD,

I stand by my advice.

End of quote.

Sincerely,

Ron

On 02/07/2011 04:35 PM, Ron Frazier wrote:
> I was listening to a Security Now podcast by Steve Gibson recently.
>
> http://www.grc.com/securitynow.htm
> http://www.twit.tv/sn
>
> I'm not sure what episode it was.  Anyway, a listener had asked a
> question about SSD drives.  Steve recommended against putting a swap
> file, or presumably a partition, on an SSD due to concerns about
> excessive wear on the storage cells, which do have a finite lifetime.
> Now, at the moment, I don't own an SSD, but it's on my want list.  I
> guess I could always put the swap on a spinning HDD.  Has anyone else
> heard anything about this specific issue?
>
> Ron
>
>    

-- 

(PS - If you email me and don't get a quick response, you might want to
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Ron Frazier

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