The Controller

Like Seagate, Western Digital didn’t make the controller inside their SSD. The SiliconEdge Blue uses a 3rd party controller but despite my prodding, WD wouldn’t tell me who made it. As SandForce has proven, the actually manufacturer of the controller is not as important as the firmware itself. That being said, I still wanted to know.

Despite having Western Digital’s logo printed on the controller, WD didn’t opt for a custom PCB on its drive:

I’ve seen this PCB somewhere before. Ah yes, PC Perspective’s review of the JMicron JMF618 based Kingston V Series SSD. Based on JMicron internals and manufactured by Toshiba, this is the latest from the company that was responsible for my obsession with weeding out SSDs in 2008. Update: Allyn tells me that the JMF618's unique feature is its support for Toshiba NAND. If you use Samsung NAND that makes the controller a JMF612.

The JMF618/612 are allegedly a lot better than the JMF602 that everyone was trying to push a couple of years ago, but this is my first experience with it. The good news is that Kingston sells its JMF618 based drive for less than $2.20 per GB. This means that we might see etailer pricing on the SiliconEdge Blue at roughly half of its MSRP.

Like most other consumer SSDs, Western Digital sets aside roughly 7% of the NAND flash on board for spare area to be used for cleaning and bad block allocation.

Sitting next to the WD branded JMF618/612 controller is a 64MB DDR2-800 DRAM made by ESMT. That’s not a ton of memory by any means, but it is ridiculously fast memory. By comparison Intel uses 32MB of PC133 SDRAM, offering 1/6 of the bandwidth. With that much memory off-chip, JMicron is most likely using the DDR2 DRAM as a cache for user data in addition to the mapping tables and block allocation algorithms. The more data you store off chip, the more bandwidth you need to service that data.


16 chips x 16GB Samsung MLC NAND Flash

Western Digital claims rights to an exclusive firmware with the SiliconEdge Blue. The initial firmware appears to be supplied by JMicron, but Western Digital has modified it to tune for compatibility. In theory that means that we won’t get the same performance out of the SiliconEdge Blue that we do from Kingston’s SSD that uses the same controller.

The JMF618/612 supports TRIM which is enabled on the SiliconEdge Blue. Western Digital won’t be offering a manual TRIM tool for non-Windows 7 OSes, stating that the performance of the drive never drops to a point where you’d need to manually TRIM it. I can’t say that I agree with that since I managed to make the drive perform quite poorly after hammering on it for a while:

But it does attempt to be fairly resilient and after being TRIMed it manages to stay very close to peak performance:

You can use the SiliconEdge Blue in a non-TRIM aware OS, but I’d recommend sticking with Windows 7 if possible.

Index Scrambling Data to Improve Reliability?
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  • Frallan - Friday, March 05, 2010 - link

    Performance isn't average its abyssimal. It can only compete with the other brands low-performance offers and is priced hicher then the High performance offers.

    I don't understand why WD turned up at the party at all - this deflates the good will that they still have.

    /F
    Reply
  • capeconsultant - Wednesday, March 03, 2010 - link

    Bigfoot? Nope. Smallfoot :) Reply
  • vol7ron - Wednesday, March 03, 2010 - link

    Anand,

    You're really pumping out the articles lately, you must be swamped!

    I just wanted to comment on your closing remarks: "It just strikes me as odd for hard drive manufacturers with decades of experience in firmware development and data access patterns, to not come out of the gates swinging."

    I'm sure you realize that the two technologies are almost completely different. Sure they have common components and similar storage logistics, but WD made it's way on the quality of the physical aspect and head speeds of hard disks.

    The comparison is almost the same as how floppy disks have been phased out by thumb drives, or film cameras being replaced with digital cameras. We didn't see those companies that excelled in the in the first generation of their technology come out swinging, did we? Verbatim and Kodak are still struggling.

    What's more surprising is not seeing a company with a big wallet to come out aiming for the fences. That's what I'd like to see, just like Intel.

    Cheers for another good article,
    vol7ron
    Reply
  • 7Enigma - Thursday, March 04, 2010 - link

    Unfortunately you must have missed the FIRST sentence of the article. They purchased a large company that had a great deal of experience in the SSD arena.

    That kind of makes your comment moot.
    Reply
  • The0ne - Monday, March 08, 2010 - link

    IF everything stayed the same than yes the point would be moot but sadly when acquisition happens changes are always in effect and mostly for the bad reasons. You can acquire the best SSD house in the world and bring it into your team with little experience in it and have them run it. Give it a few days and that "best" becomes WTF, guarantee. Reply
  • vol7ron - Friday, March 05, 2010 - link

    Haha, you do go me there. :)

    Except, SiliconSystems is really a mock company and I use that term loosely. Even if you say they focused on CF, although it is more similar to SSD NAND, as a storage product it is still significantly different. I would say, though, that the combination of WDs current storage management, combined with some experience with the NAND controllers should have put out something better than this WD SSD.

    Still, WD acquired Silicon Systems in March of last year and (even then) I thought SS was an inexperienced company. They put out Enterprise/OEM products, that didn't really deal with speed, but more with reliability; more specifically, being able to recover from unforeseen power downs, data errors, etc. While that is very important, SSDs are supposed to provide speed and that's not something SS is known for.

    So, yes, I still stand by my statement. Still different technologies and a hard transition.

    vol7ron
    Reply
  • Soltis - Wednesday, March 03, 2010 - link

    lol... these drives are on the lower end of the performance spectrum and the higher end of the price spectrum..

    But who knows? maybe with this new "reliability" WD drives will now survive the trip to your house! ~zing
    Reply
  • CTT - Wednesday, March 03, 2010 - link

    A comprehensive/insightful article, as always. I would have a couple of remarks about the graphs though: the low values are printed over the drive names and the the WD drive is listed as JM618.

    I see the TRIM support is given the due attention, but there are quiet a few users that don't benefit from it (e.g. using Windows XP, TrueCrypt). Would it be too much trouble to ask for some tests with drive full/some percent free and TRIM disabled?

    Did the WD experienced any significant (read abysmal) drop in write performance after some use (such as HD Tune Pro benchmarks at Legit Reviews and StorageReview)?
    Reply
  • Anand Lal Shimpi - Wednesday, March 03, 2010 - link

    I've been trying to figure out the best way to test performance in non-TRIM aware OSes. I'm playing around with some things and will eventually present my findings :)

    My drive didn't show any significant drop in write performance after use. That appears to be an issue with the HD Tune benchmark itself.

    Take care,
    Anand
    Reply
  • Iketh - Saturday, March 06, 2010 - link

    Yes it's an issue with HD Tune. It sometimes reports my mechincal drives as reading 1/3 of what they normally do. Reply

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