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New Device Puts SSD In a DIMM Slot

Posted by timothy on from the ram-disk-returns dept.

Vigile points out a new take on SSD from Viking Modular Solutions. The SATADIMM puts an SSD in the form factor of a memory module. "The unit itself actually uses a SandForce SSD controller and draws its power from the DIMM socket directly but still connects to the computer through a SATA connection — nothing fancy like using the memory bus, etc. Performance is actually identical to other SandForce-based SSDs though the benefits for 1U servers and motherboards with dozens of DIMM slots is interesting to say the least. Likely priced outside the realm for average consumers, the SATADIMM will likely stay put in the enterprise market but represents an indicator that companies are realizing SSDs don't need to be in traditional HDD form factors."

27 of 169 comments (clear)

  1. I suppose the real question here is... by pwnies · · Score: 4, Insightful

    Why? If it's only drawing power from the DIMM slot, what benefit does that serve? Sure, in a 1U rack it *might* save a trivial amount of space. I just dont see a market for it.

    1. Re:I suppose the real question here is... by Monkeedude1212 · · Score: 5, Insightful

      Sure, in a 1U rack it *might* save a trivial amount of space. I just dont see a market for it.

      If there's anything I've learned from calculus - it's that a whole lot of trivial values can add up to something significant.

    2. Re:I suppose the real question here is... by pushing-robot · · Score: 4, Informative

      I guess it would be a quick way to add storage to a server that has a bunch of unused memory sockets. And the design uses off-the-shelf components which is always nice.

      But there was getting to be a need for a proper SSD package, as sticking them inside HDD housings was both limiting and an inefficient use of space. Viking's solution probably won't take off, though, since Apple/PhotoFast/Toshiba just stole their thunder.

      --
      How can I believe you when you tell me what I don't want to hear?
    3. Re:I suppose the real question here is... by Anonymous Coward · · Score: 3, Interesting

      Hell yeah, this could save a megaton of space. It seems most of the negative comments are from people who have never seriously used racks

    4. Re:I suppose the real question here is... by tagno25 · · Score: 3, Insightful

      I have, and this would have a hard time fitting in a 1U case. The data cable comes out the top, but many 1U cases have the ram sticks at a 45 degree angle because they would be too tall. It would be OK in a 2U or larger and used as the boot disk.

    5. Re:I suppose the real question here is... by ElectricTurtle · · Score: 3, Interesting

      They should have model variants with connectors staggered relative to the DIMM length. Have one with the connector in the first quarter, another with the connector in the second quarter, etc. So you could have a bank of four with no cable/connector overlap.

      --
      I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
    6. Re:I suppose the real question here is... by phyrexianshaw.ca · · Score: 3, Interesting

      two words for all of you:

      custom cables.

      seriously: sata cables are cheep as hell to build, and doing a fan cable of a custom length to match up to the controller either on board or in the single 16/4x slot would only kind of make sense.

    7. Re:I suppose the real question here is... by phyrexianshaw.ca · · Score: 2, Insightful

      sure, but you know what the price of ram vs the price of flash is?

      16GB dimms run me about $900 each, whereas I can get 64GB X25-E's for $700.
      and tit for tat, the performance won't be THAT bad by comparison.
      at ~$55/GB for Ram, or ~$10/GB for flash, at 1000GB quantities... that's a pretty easy call to make personally. :P

    8. Re:I suppose the real question here is... by h4rr4r · · Score: 3, Interesting

      In a 1U server there no such space. The DIMM design lets you put it in a nice free space and not interrupt airflow too much.

    9. Re:I suppose the real question here is... by phyrexianshaw.ca · · Score: 3, Interesting

      the point is that you can instead of purchasing ram at ~$25/gb you can buy flash at ~$10/gb and still stay dense.

      I'm sure where you are there's room for things: but in much of the world this is not the case. try suggesting 4U storage cases for a customer wanting to host a 20TB database in Egypt. you may only get 4-6U in each building to work with, (with little cooling capacity) and $25K/building in hardware budget.

      There are cases for everything. I can think of a pile of customers of mine that only filled their Vmware hosts with 64GB (of the 512GB max) of ram (leaving twenty eight sockets free in each of the three hosts for something!) that's 33.6TB of space right there! (though personally I'd PREFER to stick RAM in there, that would only be another 1.344TB of ram)

    10. Re:I suppose the real question here is... by sjames · · Score: 5, Funny

      You know, there are many decaffeinated coffees on the market that are nearly as good as regular coffee without all the jitters....You should drown yourself in a vat of it.

  2. Disappointed by wjh31 · · Score: 2, Interesting

    When i saw the headline, i was hoping that this would be a device that allowed an SSD to be connected to a RAM slot and used as RAM, rather than an SSD that takes up a RAM slot.

    Additionally, if they can squeeze a 256GB into a DIMM form factor, why the are even 4GB sticks of RAM still expensive

    1. Re:Disappointed by Rob+the+Bold · · Score: 3, Informative

      Additionally, if they can squeeze a 256GB into a DIMM form factor, why the are even 4GB sticks of RAM still expensive

      Because using flash memory as system RAM would be rather disappointingly slow.

      --
      I am not a crackpot.
    2. Re:Disappointed by wierd_w · · Score: 3, Interesting

      While the write speed would be painful compared to real DRAM, the read speed would be comparable.

      For large static arrays, and for custom data applications, it could have uses in the form the GP suggests, though it WOULD be a nasty throwback to the days of user ROMs...

      However, I could definitely see the potential in having such a thing mapped directly to system memory, then loading a special block device driver to allocate all that "memory", so that memory IO could be used for data storage. It would eliminate the SATA controller's IO bottleneck, but would impose a slight CPU penalty. For systems with multiple CPUs, that wouldnt be much of a problem. You would need to allocate that memory fast though, to prevent the OS from trying to use it like RAM.

  3. Reminds of of the old hard cards by bobjr94 · · Score: 3, Interesting

    I remember back before computers had onboard drive controllers and there was no such thing as a standard drive interface, they sold ISA hard drive cards, it was a drive & controller all in one. I dont see to much advantage running a drive on a ram slot, you can just dedicate a drive(s) to you work, swap or temp files. I typically do that when editing video, 1 drive holds the raw videos, one drive is a temp drive and one is what the final video files are outputted to when they are rendered. Much faster then using 1 drive or even a single raid to read/write large amounts of data at the same time.

  4. Speedy servers by $RANDOMLUSER · · Score: 4, Interesting

    Certainly putting things like swap space and database journal files on SSD would speed things up wonderfully, but how about an OS hack where an SSD drive is a sort of L3 cache between core and traditional disk for dirty disk buffers? Also, I'm wondering about the power requirements between SSD and DIMM RAM.

    --
    No folly is more costly than the folly of intolerant idealism. - Winston Churchill
    1. Re:Speedy servers by hjf · · Score: 2

      ZFS L2ARC

    2. Re:Speedy servers by m.dillon · · Score: 4, Interesting

      Not sure I would call it an OS hack but DragonFly has precisely that, called swapcache. Swapcache Manual Page. It isn't so much making standard paging work better (systems rarely have to 'page' these days) but instead its ability to cache clean data and meta-data from the much larger terrabyte+ hard drive that makes the difference. Anyone who has more than a few hundred thousand files to contend with will know what I mean. -Matt

  5. Because RAM isn't Flash by Sycraft-fu · · Score: 3, Informative

    The price of flash has nothing to do with the price of RAM. They are completely different constructions, and for different tasks. Flash is faster than magnetic storage but still dog slow compared to RAM. For flash you talk access time in 2-3 digits of microseconds. For RAM you talk access time in single digit nanoseconds. For flash transfer rates are in the 100s of MB/sec with anything over 200 being rather exceptional. For ram transfer rates are in the 10+GB/sec.

    Same sort of transition again when talking DRAM (what you put in your system) to SRAM (what processor cache is made out of). Again the price goes up massively so instead of 8GB, you are talking maybe 12MB. However again the speed goes way up and access time way down.

  6. saves space primarily by Chirs · · Score: 2, Informative

    It's aimed at 1U servers that have no free drive bays or PCI slots.

  7. Mini Options! by Falc0n · · Score: 4, Interesting

    Actually I find this potentially quite cool. Not as much for the power source, but the size. Since most mATX boards don't come with mini PCIe slots, if you want to use an SSD drive you need a 2.5" drive or a PCIe card with a mini-slot on it. Both are much larger than a DIMM option.

    And with 50gb, this would be very useful in a media box streaming from a server. Now only if the price could come down.

  8. Why so many ignorant replies? by PatPending · · Score: 2, Insightful

    I can't recall a /. story that has this many ignorant replies.

    Aside from the usual lack of RTFS and not reading TFA, I wonder if it's due to ignorance of hardware?

    --
    What one fool can do, another can. (Ancient Simian Proverb)
  9. Re:kinda dumb by DarkXale · · Score: 2, Informative

    You basically completely failed to look at the difference in size, or consider the type of case it is mounted in. Sure its unnecessary in a traditional Tower Case, where there are often 8 hard drive slots available. But in a small server rack where space is premium; this becomes very viable, especially as there are often few drive slots available; but probably there are unused RAM slots.

  10. Useless with virtualization? by ferrocene · · Score: 4, Insightful

    This device seems backwards with today's trends. With virtualizaion gaining ground fast, the ideal setup is to have as much RAM as possible with a SAN back end for storage - iSCSI, FC, whatever. Most local disks on servers today are RAID1 mirrors for the small hypervisor.

    So, yes, this device wastes a valuable DIMM slot to give you a less-valuable SATA drive?

    I can't think of any scenario where this would be useful unless you're talking about handheld devices - a MacBook Air or tablet of some sort.

    --
    Most folk'll never lose a toe, and then again some folk'll...
    1. Re:Useless with virtualization? by h4rr4r · · Score: 2, Insightful

      DB servers in a leased rack. Doing DB IO over FC or iSCSI adds latency that local disks are not going to have. This gets you fast local storage without having to pay more each month for leased rack space.

      Virtualizing high performance DBs is a stupid move.

  11. New? by Lumpy · · Score: 3, Funny

    I've had such things in the embedded world for over a decade.

    What's next? NEW! small cards serve as memory devices!

    --
    Do not look at laser with remaining good eye.
  12. Re:Just an SSD that uses memory slot power? by phyrexianshaw.ca · · Score: 2, Informative

    except storage capacity. they're 512GB (raw, 400GB formatted) per Dimm. making them 32 times denser capacity vs RAM.

    though yes, you're right: compared to the equivalent AMOUNT of RAM, they suck. compared to the same dollar value of ram: that's another story.