SSD scratch disk life span?

jfklimek

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Would it be detrimental to the life span of a SSD if it were used for a scratch disk? I'm building a workstation computer used fro Adobe + CAD + 3d Rendering Softwares. I want to provide a general RAID 0 2x2tb hdd for main data, 1 ssd for os+programs, 1 ssd for scratch disk. The plan is to provide a smaller 40 - 64gb ssd for the scratch disk. I got several concerns with this choice:

1. Will it shorten the lifespan of modern SSD's with TRIM on Windows 7.

2. Would it be smart to focus on a SSD that is equal in read/write? (I've seen the read is usually much less than the write speeds... this is good for OS + Program setups where reading is the most important but isn't scratch disks heavy read/write operations?)

3. Would my system's performance benefit more if I put the HDD's or SSD's to a SATA III connection (which one would be smarter to put to the 6gb/s connection vs. the 3gb/s connection... I have two 6gb/s spots available = 1x Raid0 HDDs or the two SSDs).

4. Any recommendations on either HDD or SSD that would be preferable for a scratch disk is much appreciated.
 

randomizer

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Of course it will shorten the lifespan. It's the same with any disk, SSD or spinner. The more you use it the shorter its lifespan. I'm not sure the 6Gb/s connection will actually provide any benefit. I vaguely remember reading that most current SATA III implementations are pretty poor, but I'm not absolutely sure. Without knowing what motherboard you're using it's impossible to make that call about your system anyway.
 
SSDs have an absolute write limit beyond which they start failing to accept new data (unlike hard drives, whose mechanical parts may or may not wear out faster with heavier use, see the Google study on disk failure rates). So the more you write to an SSD, the faster it will wear out.

Using an SSD as a scratch disk will tend to subject it to more writes, since files that are written to it are used only briefly and then deleted (unlike an OS disk, whose files are written to the drive and then are re-read many, many times).

That having been said, whether it's a big issue or not depends on how much writing you do. Intel claims their X-25M G2 drives will last "at least" 5 years if you write 20GB/day to them. The Intel SSD Toolbox shows how many GB have been written to the SSD, and my Windows 7 system is averaging about 5GB/day. Even if that was doubled as a result of scratch file writes then you'd still be looking at about 10 years of life, by which time the drive would be pretty much obsolete anyway.
 

blackhawk1928

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^If intel says 20GB per day=5 year lifespan...i don't even do over 1GB...probably much less. MY SSD is going to live a long life.

OP=Even if you use it as scratch disk, i'm willing to bet its going to last longer than an SSD is :) Unless you literally write tons of GB's of data 24/7. Also, this is assuming a good quality SSD is used. And if you use an SLC SSD...then its cell cycle is said to be 100,000...so it will absolutly outlast an HDD i think.
 

Wamphryi

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There are two issues here that need to be taken into account. The first is that a Scratch Disk usually requires a great deal of capacity. SSD are not famous for their capacities. If you intend on using AVI format or HD at any stage then you will be looking at some serious GB usage. The second issues is that a Scratch Drive usually adds to performance on machines with small RAM configurations. These days with 4 GB RAM machines becoming the norm it is unlikely that a Scratch Drive will provide any increase in performance. The most I have ever seen my drives read / write during editing is 25 MB read and 25 MB write a second. I tested a project by running it using 2 WD Greens in RAID 1 , Velicoraptors RAID 0 and a RAM Drive I set up. There was no difference in performance. Forget trying for performance especially if your machine is something like an i series with 4 GB RAM. Think capacity and redundancy and you will be spending your money well. Try a couple of Seagate Barracudas at 1 TB RAID 1. You will be much better off.
 

MRFS

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I know I'm in the minority on this issue, but
I'd highly recommend 2 of these WD5003ABYX in RAID 0:

http://www.newegg.com/Product/Product.aspx?Item=N82E16822136697&Tpk=N82E16822136697


ATTO consistently reports 150 MB/second at the outermost tracks
and this HDD is truly Plug-and-Play!

However, WD does NOT report this measurement in their specs:
they prefer to report a "sustained" rate which is usually quite lower:

http://www.wdc.com/wdproducts/library/SpecSheet/ENG/2879-701338.pdf


So, "short-stroke" a smaller primary partition
e.g. 50 GB total will use only the first ~25 GB on each HDD:

http://www.supremelaw.org/systems/io.tests/platter.transfer.crossover.graphs.2.png


Perpendicular magnetic recording not only records bits closer together;
it also permits adjacent tracks to be much closer to each other as well.


MRFS
 

MRFS

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> Would my system's performance benefit more if I put the HDD's or SSD's to a SATA III connection

Hitachi make some really fast 2.5" SAS HDDs with a 6G interface
and a very large cache e.g.:

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=Hitachi+2.5%22+SAS&x=0&y=0


This is a modern yet inexpensive PCI-E x8 Gen2 SAS RAID controller
that works well with those Hitachis:

http://www.newegg.com/Product/Product.aspx?Item=N82E16816115079&Tpk=N82E16816115079


There are now several 4-in-1 enclosures for these 2.5" HDDs
that fit into a single 5.25" drive bay e.g.:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817994095&Tpk=N82E16817994095

http://www.enhance-tech.com/press/press_082509_QuadraPack_X14.html


But, you'll need this "fan-out" cable because the RR2720 comes
with a different cable that connects to a backplane:

http://www.newegg.com/Product/Product.aspx?Item=N82E16816115064&Tpk=N82E16816115064

The 2 enclosures above have standard SATA connectors
on their rear panels, so the latter cable will work with those
4-in-1 enclosures and the RR2720 installed in an x16 or x8 PCI-E slot.


MRFS
 

jfklimek

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Do scratch disks really require much space. I was intending t to buy a 40 - 80gb sized drive to take care of the space i needed for 'scratch'. I'm not sure I'm aware of what the scratch disk sizes need. I edit some large .tiff + .raw files but i didn't think i was going to need more than the size listed above. From the sounds of it I need about 500gb for 'scratch' space. This is super large from what I thought i needed. can anyone tell me why so much space is needed or at least being recommended to me. I'm not doing much AVI or HD work. Just static stuff.
 

Wamphryi

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Scratch Disks do require space and HDD technology at 1 TB is very affordable. What you need to keep in mind is that there is no real performance gain to be had anyway unless you are running a P4 with 256 MB RAM in it or something. I could not get any gain using RAM Drive over a couple of WD Greens in RAID 1. SSD is complete overkill and lacks the space that will be consumed by Video Editing tasks. Even if you dont do much AVI or HD work right now, the moment you do you will encounter space issues. The reason why I suggested a 1 TB kit is because the price difference between some 1 TB drives and some 500 GB drives is next to nothing. Also completed work has to be stored and that should be on a RAID 1 array unless you like losing hours of work to HDD failure.
 
It totally depends on what you're doing. Movie editing tends to require a LOT of scratch space. Editing photos, RAW or otherwise, shouldn't require a whole lot if you edit one at a time. But if you try to stitch together a large panorama from dozens of shots then it'll be a different story.

The best thing to do is to configure the scratch files onto an HDD and watch what happens to its free space as you do what you consider to be the heaviest editing job you expect to handle. The drop in free space should give you a pretty good idea of how much scratch space is being used (assuming you're not doing something else like downloading files from the Internet at the same time).
 

jfklimek

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okay thanks for those answers. I'm mainly concern with the heavy read/write processes ruining my storage drives. Should this be a worry... should a scratch disk be isolated? Is a 1tb(non-raid) samsung f4 sound like a good choice?