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Samsung HDD Merges Flash, Conventional Storage

Posted by timothy on from the layering-the-layers dept.

geekboxjockey points "This is a link to a story about a hybrid hard-drive technology from Samsung that involves the use of flash memory and conventional storage. A very interesting idea that could provide noticeable energy useage/speed improvements for HDD-based portable devices."

10 of 152 comments (clear)

  1. Swap File by eXzite · · Score: 2, Interesting

    Will the OS have a way of selectively writing to the flash? What about swap files, etc, which will change all the time?

    This is great stuff though, swap files aside, most people could probably do everything they ever need from their laptop within 1Gig of flash, during a single work session.

    1. Re:Swap File by MSZ · · Score: 3, Interesting

      For Linux, sure.
      For Windows, not unless they replace the memory management. It normally uses swap even when there's plenty of free memory and this is supposed to be a feature, not a design bug...

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  2. A gimmick by Saven+Marek · · Score: 3, Interesting

    flash memory like this in a hard drive is a gimmick, I think samsung are hoping nobody realises how few the write times are on flash memory, so you'll need to regularly replace the limited write time flash memory when it's worn out fairly often

    So what happens when trying to detect when the flash memory has been written to too many times? afaik this isn't easily done, so you end up dumping broken data to the disk until you notice "whooops my spreadsheet suddenly doesn't work that I need in 30 minutes or the boss will have my ass".

    1. Re:A gimmick by oc255 · · Score: 2, Interesting

      Gimmick? Hmm...

      This is just electronic writes. Those who have worked with a high-performance SAN like the Hitachi 9900, Sun 6920, know that electronic writes is where all the performance comes from. When our SAN's 4gig of cache goes offline, my DBAs come running and everyone complains about terrible write/read speeds.

      Electronic writes (in a good amount) means that the data flies into memory and later on the disk system pumps the data out to the disk platters. Netapp is really great at doing this kind of operation. Talk to someone with a Netapp and they'll tell you that you can watch all the activity lights on an array light up in a fury of activity with the Netapp head pushes from cache->disk. It's really fantastic. Of course, it's really expensive too.

      I'm not saying that Samsung's disks are going to be enterprise-class. But I'm hoping that this cache thing catches on to make SATA2 (or whatever) based arrays feasible for desktops. Imagine a chain of large-cache drives on desktops, large-cache single drives on laptops ... For example, if you had 128MB of cache per drive, then an array of 8 disks would have 1gig of cache. That would be so great for the power-user. The Sun T4 bricks cost $50k and they have 2gb of cache per controller. 2gb of electronic writes/read = amazing performance.

      I can't wait to learn more about the quality and speed of the disk cache. It's what I've always wanted to see in consumer grade disks.

  3. software implementation... by Nova1313 · · Score: 2, Interesting

    Isn't this already implemented in software in some form. As memory cache of sorts. I understand that with memory if you loose power you loose data so this just seems to act as a bridge. What happens if the power goes out and data has yet to be written but is in flash. Is what is in there automatically committed to the disk on the next power up? The article doesn't go into much detail unfortunately. It seems like a good idea if implemented properly but for me everytime I launch a new copy of explorer on a windows box it has to spin up the disk. So unless you keep the most frequently used applications in memory I'm not sure this will cut down on writing except for with small data files being saved.

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  4. FROM Here to Eternity by Doc+Ruby · · Score: 3, Interesting

    How about booting from the HD, then "caching" the computed startup image in the FROM? At shutdown, store kernel/OS variables in a table. At next boot, just suck in the image from FROM, and update runtime changes (clocks, counters, etc) from the table. Corrupt images get dropped by rebooting from HD when necessary. It's like notebook "hibernate", but stores the "clean" initial boot state instead of the (possibly corrupt) final OS state. Linux's initrd boot ramdisk phase offers a golden opportunity to just restart from the image cached in quick FROM. If Samsung patched the bootloader, it could sell a lot of these drives. I'd pay as much for a 100GB platter-only drive as I would for a 40GB boot hybrid drive.

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  5. Read/Write times by blueadept1 · · Score: 0, Interesting

    Correct me if I'm wrong, but wouldn't a flash-based hard drive have quite a bit (~2x) slower write and read times? Perhaps if it was built into the architecture to be 'closer' to the processer such as RAM is.

    This seems like they are just trying to turn RAM into a permanent storage device.

    I really don't see any advantages to this as it is. Even the prices would be higher.

  6. What's so innovative about it? by DrLex · · Score: 2, Interesting

    So if I get it right, this is just a drive with a very large, albeit slow, memory cache. They expect the users to address their data in separate chunks of 128MB. As soon as you go outside of this chunk you'll have to spin up the drive to read the file -- which will, of course, reduce the responsiveness of the system. Moreover, drives don't only wear out due to the disk spinning. Every spin-up and spin-down cycle causes additional wear, so I doubt this idea will reduce the failure rate for laptop disks. Actually this article looks more like publicity for Longhorn...

  7. Re:Actually this story isn't entirely accurate by ScrewMaster · · Score: 2, Interesting

    Yes, I've burned up several flash sticks because I write to them constantly at work (usually 60-100 Mb application setup sets) so I can attest to the limited number of write cycles. Ordinary DRAM parts aren't suitable for battery backup unless you include refresh logic and in any event they always draw substantial amounts of power. The solid-state drives I've used have CMOS static RAM on them. CMOS logic gates don't draw much current unless they're in transition, which makes them ideal candidates for long-term battery standby. Being true RAM (instead of flash, which is basically just a modified EEPROM anyway) there's no particular limit on the number of reads or writes. On the other hand, they don't have the bit density of dynamic RAM, and the cost per bit is much higher. But they still are excellent for industrial applications where you want reliability (harsh environments of one kind or another) or where a system has to boot very rapidly.

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    The higher the technology, the sharper that two-edged sword.
  8. Re:Hardvaporware ? by TylerL82 · · Score: 1, Interesting

    ...of course, you could also say...

    Apple was the first mainstream manufacturer in the industry to implement USB into their systems (iMac, May/August 1998).

    Apple was the first mainstream manufacturer in the industry to implement FireWire/IEEE1394 into their systems. (January 1999, Blue and White Power Mac G3)

    Apple was the first mainstream manufacturer in the industry to implement DVD burners into their systems (the original SuperDrive, DVR-103, was introduced in January 2001 alongside the Pioneer DVR-A03. The drive was the first commercially-available burner for DVD-R General discs).