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Data Storage Upgrades Hardware

OCZ Wants To Cache Your HDD With an SSD 189

sl4shd0rk writes "OCZ is coming out with Synapse Cache; an SSD cache for your hard drive. The SSD runs software that copies data into the cache from your hard drive as you work with it. The data sits on the SSD until it gets less activity and gets flushed to the hard disk. Aside from boosting your IOPS to 10k/75k (read/write), the SSD also supports AES encryption, SMART and TRIM."
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OCZ Wants To Cache Your HDD With an SSD

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  • Its ZFS for Windows then?

    • Re:So... (Score:5, Funny)

      by Bill, Shooter of Bul ( 629286 ) on Friday September 23, 2011 @12:05PM (#37493542) Journal

      Exactly! ....In the same way that a meatball is a golf ball for those playing the game of spaghetti.

    • Windows ReadyBoost would work about the same way as ZFS's l2ARC if it allowed using whole SSDs instead of flash drives. It's basically the same idea, a second level page cache that can be removed or fail at any time.

      Why desktop PCs continue to be built with the 'one large spinning disk one small SSD for important stuff' design while desktop operating systems totally ignore the potential of using them as cache boggles my mind.. I swear it is a conspiracy to make people buy larger SSDs than necessary instea

      • by arth1 ( 260657 )

        Windows ReadyBoost would work about the same way as ZFS's l2ARC if it allowed using whole SSDs instead of flash drives. It's basically the same idea, a second level page cache that can be removed or fail at any time.

        No, it's not the same. ReadyBoost provides a compressed paging file cache, it doesn't work as a cache between the OS and the HD.
        In other words, it only gets what is written to the paging file, or pages that are dropped from memory. Combined with SuperFetch, ReadyBoost gives a good boost in starting applications, but it neither works as RAM (the most common misconception), nor does it increase disk write speeds.

        That said, Windows already has an API for hybrid disks, with both SSD and HDD that does what thi

        • by drsmithy ( 35869 )

          No, it's not the same. ReadyBoost provides a compressed paging file cache, it doesn't work as a cache between the OS and the HD.In other words, it only gets what is written to the paging file, or pages that are dropped from memory.

          That's not how Mark Russinovich describes it here. [microsoft.com]

          "After the ReadyBoost service initializes caching, the Ecache.sys device driver intercepts all reads and writes to local hard disk volumes (C:\, for example), and copies any data being written into the caching file that the servic

      • Prepare to have your mind unboggled:

        For most people, the OS has been fast enough for the last decade. Boot times happen once per day at the most, programs launch once or twice per day and reside in large amounts of fast RAM. Even games reside just fine in 12GB of DDR3 and run like a champ on mid grade video cards. Where the speed breaks down for home users is Photos and Video. Everybody and their mom has digital photo and video equipment that fits in a purse or pocket.
        It's working with these files where

      • Comment removed (Score:4, Interesting)

        by account_deleted ( 4530225 ) on Friday September 23, 2011 @01:47PM (#37494830)
        Comment removed based on user account deletion
        • so while using it as a cache (as long as the cache is ALWAYS backed up like Readyboost) sounds fine i really can't see recommending an SSD until they get the bugs out. you would have to spend all your time running back ups or RAIDing the drive constantly to remove the risk, and that is just more trouble than its worth

          Not really, with decent software. Here's my primary SOHO server's vm storage array, on ZFS:

          NAME STATE READ WRITE CKSUM
          storage DEGRADED 0 0 0

        • by nigelo ( 30096 )

          Just think of the time you will save, though, by immediately deciding to retrieve from backup, as opposed to copying files, worrying about bad sectors, hoping the drive doesn't completely fail while you are copying, etc,etc.

        • so while using it as a cache (as long as the cache is ALWAYS backed up like Readyboost) sounds fine i really can't see recommending an SSD until they get the bugs out. you would have to spend all your time running back ups or RAIDing the drive constantly to remove the risk, and that is just more trouble than its worth. Besides with Superfetch and Readyboost if you have a large amount of RAM (and what geek don't right? hell even my netbook is gonna have 6Gb on it) then everything you use often is already preloaded into RAM so unless you boot daily i doubt you'd see much difference, as nothing yet beats RAM speed.

          The idea is you're unlikely to find 64+G of ram in a desktop, and it could potentially be persistent. Backups and RAID have nothing to do with this, a SSD used as page cache can have a failed read or write at any time and the OS wil just move on.

          I think they make perfect sense as a page cache in desktop systems.

        • To me it isn't THAT they fail it is HOW they fail that has me avoiding them. With HDDs I can't remember the last time I had an HDD that failed without plenty of clear warnings something was up. Windows delayed write fails, or SMART errors, temp going nuts, there was ALWAYS a clear warning that there was trouble in HDD town. With both of the gamers there was NO WARNING with the SSDs, they just flipped the switch and....nothing. With the HDDs I was always able to get the data off before they bought the farm, minus a few bad sectors of course, but with the SSDs it was like they didn't exist, it was just...nothing.

          Storage failures are nothing new... Google claims most HDD failures don't show any signs [engadget.com] on SMART before going off. Add to this the fact that anyone not running with a bootable up-to-date backup (all OSs have cheap or free backup tools that create bootable backups) is asking for trouble. I've had HDDs fail without any warning (mostly on corporate systems). I've also had systems stolen (laptop), and the up-to-date backup was a life (and work) saver.

          I own 3 SSDs now that work well and have yet to fail (s

      • No. More like Eboostr
        www.eboostr.com/

    • On this topic, does anyone know how to set up something like an unRAID cache drive [lime-technology.com] using only FOSS tools? bcache is the closest thing I've seen and it's not really the same thing either.

  • by zaibazu ( 976612 ) on Friday September 23, 2011 @12:04PM (#37493514)
    They need to make the controller logic bullet proof, Seagate had quiet some problems with their hybrid disks
    • by fuzzyfuzzyfungus ( 1223518 ) on Friday September 23, 2011 @12:24PM (#37493822) Journal
      A best I can tell, this is simply a basic SSD that is shipped with a bundled OEM copy of "dataplex" software from these guys [nvelo.com](nice clip art...) (Here is a presentation by them about their product [flashmemorysummit.com].

      The SSD itself is a Sandforce 2281-based MLC drive with 50% overprovision for redundancy. Unless they've really screwed the firmware, it should be just fine, though no word on how it competes in price with other drives of similar size.

      The caching function(unlike the Seagate hybrid units) is simply software: Supports Windows 7, no BIOS goo or specialized SATA features required; plugs into the OS somewhere in the storage handling area and shuffles data between the main mechanical HDD and the designated cache SSD.

      On the plus side, that should(at least conceivably) give it considerably higher-level knowledge of what the OS is doing with which to make caching decisions(unlike caching firmware, which only has the SATA commands to go on). On the minus side, it means Win7 only, and your storage system is Not the place you want potentially flaky code, so if they aren't on the ball, we could see some serious bluescreening and/or OS hosing going on....
      • by gknoy ( 899301 )

        Would that kind of software be available so that I could do that with my own SSD+HD? I currently have an SSD that I keep gaming stuff on, but I wouldn't mind repurposing it as a cache if I knew how. Is there an easy way to do this?

        • I'm not sure. ZFS as support for using an SSD or SSDs as cache in a larger storage pool; but the phrase "that I keep gaming stuff on" usually does not imply "I run Solaris/BSD/Linux with ZFS/FUSE". In Linux, btrfs either has, or is working toward, some sort of SSD optimizations, I'm not certain how close they are to ZFS'.

          Most of the reasonably nice SANs and storage appliances have support for some similar caching thing, to RAM, SSD, or a combination; but "Buy a SAN and bootable HBA" isn't exactly a deskt
        • Would that kind of software be available so that I could do that with my own SSD+HD? I currently have an SSD that I keep gaming stuff on, but I wouldn't mind repurposing it as a cache if I knew how. Is there an easy way to do this?

          www.eboostr.com/

  • Modern operating systems do that automatically anyway, as long as there's free RAM. It'd probably be less expensive to add another 32-64GB of RAM to your PC, than it would be to buy dedicated hardware to do that job.
    • by EdZ ( 755139 )
      A 64GB SSD is about £100 nowadays. 64GB of RAM (ignoring the price of a motherboard with enough slots in which to fit it) is closer to £320 (buying cheapest-of-the-cheap 2gb stocks).
      • For servers that would possibly be worthwhile, but I'm not sure why a home user would need 64GB of cache. 2GB would probably more than enough. Folks needing more than that would probably just opt for a 64GB SSD and be done with it.

        • I use all of 16 gb of ram as an advanced home user doing video editing (by no means am I a pro).
          That said, I use spinning disks for the video work because I amd rewriting blocks all the time with scratch and render files and while an SSD is faster, it's not enough to make up for the killing of the drive in short order (which I've already done once).
          -nB

      • by fnj ( 64210 )

        Who uses 2GB sticks to get 64GB anyway? You can get a 4GB high quality stick for $21.99 at Newegg [newegg.com]. That's $351.84 for 16 of them. That's £227 at today's exchange rate. You're right about the ratio, though. It's about 3:1 for price of RAM to SSD.

        And you know what? I'd take the RAM in a heartbeat. It would have at least 10:1 better read rate, and even more advantage in write rate. It never wears out. And you can use it for anything; not just a hard drive cache. In fact, I'd say the sweet spot

      • I just bought 8 GB high-end (1600Mhz DDR3) RAM for 30 quid. That makes 240 for 64 GB.

    • Why would you want to cache your RAM to an SSD? :P
    • by myurr ( 468709 )

      No. The problem with caching in RAM is that it is volatile so if the power fails you'll lose the changes. Where this SSD helps is in providing a speed boost over a magnetic hard drive but without the volatility of RAM. The RAM cache will still be used to provide a further speed boost, but when a program issues an fsync to make sure that all the data held in the RAM cache is flushed to a physical disc, it will be the SSD that is picking up the slack.

      For a read heavy environment with lots of RAM that is ha

      • by h4rr4r ( 612664 )

        The cost of going all SSD?
        Have you priced SSDs recently?
        You can get 100GB drives for ~$150. How much cheaper does it have to be?

        Sure you might still want a few spinning drives for bulk media storage, but that can be in one machine in the house not all of them.

        • by myurr ( 468709 )

          So that's ~£1,500 per TB. Yet you can get a 1TB drive for less than the 100GB SSD... That's a HUGE discrepancy for bulk storage where the speed of retrieving every last byte doesn't matter.

          This technology has its place for now and provides a welcome speed boost for those unable or unwilling to invest in a full SSD solution for their bulk storage needs. Going all SSD is the best solution for some people; going all mechanical is best for others; and there's a whole range of people with needs in betwe

          • by h4rr4r ( 612664 )

            Put the mechanical drives in another machine and use that for dedicated storage. All the other computers can have nice fast SSDs.

    • Modern operating systems do that automatically anyway, as long as there's free RAM. It'd probably be less expensive to add another 32-64GB of RAM to your PC, than it would be to buy dedicated hardware to do that job.

      This doesn't help you when you need:

      1: Access to a file or files totaling more than 64 GB (or however much ram you have for caching)
      2: Files not yet cached

      Mostly I'm thinking games is where FS caching is less than optimum, since some of the resource files can easily exceed the amount of system memory available and if you like being competitive, the faster you load the game the better... and the FS cache won't help you there.

      You also run into the problem of most motherboards don't support more than 8 GB (for

      • Comment removed based on user account deletion
      • This doesn't help you when you need:

        1: Access to a file or files totaling more than 64 GB (or however much ram you have for caching)
        2: Files not yet cached

        Neither does a 64GB SSD, brainiac.

    • Umm, are you aware just how expensive 32GB of RAM is? It isn't quite as pricey as I was expecting, Newegg has 24GB of DDR3 for as low as $160 (holy shit RAM is getting cheap), but that assumes you have 6 RAM slots, and I've not seen a consumer board with more than 4. If you want 8GB DIMMS (for 32GB on a consumer board), you're looking at more like ~$800 USD for 4. On the other hand, a 120GB SSD is around $160. Build a 64GB into a HDD, and it's still cheaper than anywhere near that in RAM.

      The whole idea is

    • Quick Google says:
      64GB SSD = $86
      64GB RAM = $2000

      • by fnj ( 64210 )

        Maybe you could join the 21st century sometime. 64GB of RAM costs 16x$21.99=$351.84 [newegg.com], not $2000.

        • Maybe you could join the 21st century sometime. 64GB of RAM costs 16x$21.99=$351.84, not $2000.

          I think you'll need to be a bit more specific with the time period.

    • RAM cache is not persistent. That means when a user writes to a file, the system cannot (usually) return immediately after it's copied into cache; it must wait until the data is persistently stored. Thus slow persistent storage (HDD) is still a bottleneck even with lots of cache. (If you are doing non-blocking writes to a 64 GB non-persistent cache you could lose the whole system in a crash! Simply flushing that cache to disk could take an hour - does your UPS last that long?)

      Also, the amount of disk

      • does your UPS last that long?

        mine lasts 40 min.
        I still don't trust cached writes.

      • by fnj ( 64210 )

        You have inaccurate knowledge of how caching works. Normally, write calls return as soon as the data is written to RAM, which is VERY quick. Writing back to hard drive then occurs in the background. Isn't multi-tasking great? You have to take special measures in your file I/O calls if what you want is to not have the system return until the data reaches the hard drive. That is very seldom appropriate or necessary, though you can do it.

        It will never be necessary to wait an hour for writeback because the

  • by c0l0 ( 826165 ) * on Friday September 23, 2011 @12:10PM (#37493614) Homepage

    Intel is doing the very same thing on their most recent "enthusiast" desktop chipsets.

    For systems using the Linux kernel, there are software implementations of the very same block-level-caching-concept available - one I stumbled over is http://bcache.evilpiepirate.org/ [evilpiepirate.org]

    • Intel is doing the very same thing on their most recent "enthusiast" desktop chipsets.

      For systems using the Linux kernel, there are software implementations of the very same block-level-caching-concept available - one I stumbled over is http://bcache.evilpiepirate.org/ [evilpiepirate.org]

      ... Make no mistake, this should be the job of the operating system. Solaris has zfs l2arc, and Windows has ReadyBoost that is similar. Windows and Mac systems both ship with the big disk little SSD pattern. MS and Apple need to get off their asses and ship 'SSD as cache' software like Sun did. Only reason I can think of for not doing this is patent disputes, some angle that makes this not feasible for desktop use, or an intentional long term strategy to drive SSD costs down by poising them as spinning

      • by BrentH ( 1154987 )
        I agree it makes for sense for an operating system (filesystem perhaps) to do this job. Unfortunately, Windows does not do it. Readyboost is merely an extra space for Superfetch to cache files, but this isnt persistent over reboots. So every time I boot, I have to retrain the cache, which is about as undesirable as a filesystem cache could be. If not sure if software like eBoostr solves this, but if anyone has a Windows alternative, much obliged.
        • "but this isnt persistent over reboots"

          Agreed, the current implementation sucks, and it has to be coaxed into using a SSD as opposed to a thumb drive too. My point is it is so danged close... I don't understand why MS stopped with it where they did.

          Short term solution I'd propose is.. why do people avoid low power / sleep states so much in Windows? They need to fix that..

          • by BrentH ( 1154987 )
            So what do you think of eBoostr? I've been thinking of expanding my (5400rpm) system with a 16/32GB SSD as some sort of cache. Readyboost has its downsides, but I understand that eBoostr makes the cache persistent. Apart from a few forum posts, I cant find any proper benchmarks of it from the big hardware sites.
    • For Intel board, you have to have a Z68 chipset. Those are quite new and only available on certain boards. If you happen to have a P67 chipset, as I do, you are out of luck. All the standalone solutions up to now have been enterprise RAID card that are extremely expensive.

      So something standalone would be nice. I'd look in to this, if I hadn't already taken the plunge and simply bought enough SSD storage to meet my needs. This is a much more economical option though.

  • Comment removed (Score:4, Interesting)

    by account_deleted ( 4530225 ) on Friday September 23, 2011 @12:20PM (#37493760)
    Comment removed based on user account deletion
    • Re: (Score:3, Informative)

      by fdawg ( 22521 )

      Obv I have no idea how OCZ plans on doing this, but I can tell you what a standard journaling fs does.

      In any event, how well can this device recover from a dirty-cache shutdown?

      Chances are this cache is transparent. The blocks translate to vblocks which map to physical blocks on the rotational media. A "dirty" block is a vblock which hasn't been committed to the physical block. However, this is transparent to the filesystem. When the system comes back up and the journal is replayed at say, some operation 10, and we find the relevant blocks for op 10 which happen to be vblocks

    • Since the SSD is non volatile I'm not really sure what a system lockup would do. If the byte(s) writes to the SSD and the system fails it is still on the SSD. When the system boots up the thing would be considered dirty and would write it out to the hard drive. I'm sure they will have to reserve blocks of data for dirty bits... a byte can store 8 bits each bit representing a much large ...like 64k block in the cache. A 1 means dirty a 0 clean or vice versa.

      The same basic thing has been around for SCSI RAID

    • Not sure I'm feeling the love for this concept. On the reads, sure. Nice idea. Writes however, not feeling the love.

      You wouldn't do that, you would cache writes to RAM like you do now. If you NEED multiple gigs of write cache, stop running that application on a desktop...

  • While good it is not all there is to it. SSDs benefit from the same process shrinking as CPUs and GPUs do.

    For fun I created a this table which predicts what processes will be available in the future based on numbers from Wikipedia. They are all in nanometer, and should not be trusted for anything beyond 2011 :)

    1971: 9095.3066, 1972: 7865.412, 1973: 6801.8275, 1974: 5882.064, 1975: 5086.6737, 1976: 4398.8385, 1977: 3804.0144, 1978: 3289.6242, 1979: 2844.7913, 1980: 2460.1101, 1981: 2127.4467, 1982: 1839.767,

    • While good it is not all there is to it. SSDs benefit from the same process shrinking as CPUs and GPUs do.

      For fun I created a this table which predicts what processes will be available in the future based on numbers from Wikipedia. They are all in nanometer, and should not be trusted for anything beyond 2011 :)

      1971: 9095.3066, 1972: 7865.412, 1973: 6801.8275, 1974: 5882.064, 1975: 5086.6737, 1976: 4398.8385, 1977: 3804.0144, 1978: 3289.6242, 1979: 2844.7913, 1980: 2460.1101, 1981: 2127.4467, 1982: 1839.767, 1983: 1590.9882, 1984: 1375.85, 1985: 1189.8034, 1986: 1028.9147, 1987: 889.7817, 1988: 769.4628, 1989: 665.4137, 1990: 575.4345, 1991: 497.6225, 1992: 430.3325, 1993: 372.1417, 1994: 321.8196, 1995: 278.3022, 1996: 240.6693, 1997: 208.1253, 1998: 179.982, 1999: 155.6443, 2000: 134.5976, 2001: 116.3969, 2002: 100.6574, 2003: 87.0462, 2004: 75.2755, 2005: 65.0965, 2006: 56.294, 2007: 48.6817, 2008: 42.0989, 2009: 36.4061, 2010: 31.4832, 2011: 27.2259, 2012: 23.5444, 2013: 20.3606, 2014: 17.6074, 2015: 15.2265, 2016: 13.1675, 2017: 11.387, 2018: 9.8472, 2019: 8.5156, 2020: 7.3641, 2021: 6.3683, 2022: 5.5072, 2023: 4.7625, 2024: 4.1185, 2025: 3.5616, 2026: 3.08, 2027: 2.6635, 2028: 2.3033, 2029: 1.9919, 2030: 1.7225, 2031: 1.4896, 2032: 1.2882, 2033: 1.114, 2034: 0.9633, 2035: 0.8331, 2036: 0.7204, 2037: 0.623, 2038: 0.5388, 2039: 0.4659, 2040: 0.4029, 2041: 0.3484, 2042: 0.3013, 2043: 0.2606, 2044: 0.2253, 2045: 0.1949, 2046: 0.1685, 2047: 0.1457, 2048: 0.126, 2049: 0.109, 2050: 0.0942, 2051: 0.0815, 2052: 0.0705, 2053: 0.0609, 2054: 0.0527, 2055: 0.0456, 2056: 0.0394, 2057: 0.0341

      The point is that these numbers will help SSDs, too.

      And you reach the atomic level when...?

    • The current trend in flash process size reduction is to trade off erase endurance for the additional area shrinkage in pretty much a linear fashion.

      So while the smaller tech allows for larger capacity drives in the same form factor, for two drives of equal capacity, equal over-provisioning, but different process sizes, you are much better off (in terms of erase endurance) with the larger process size.

      I believe the latest shrink cut the erase endurance by approximately half, while approximately doubling
    • by afidel ( 530433 )
      Uh, one big problem with NAND flash is that as you shrink the wall thickness you decrease the write endurance. MLC flash already has pretty poor write endurance at 1,000-10,000 cycles so managing the tradeoff between write endurance and capacity is going to be a major problem over the next 2-3 process shrinks, forget all that garbage that goes below the size of a silicon atom....
  • by wisebabo ( 638845 ) on Friday September 23, 2011 @12:30PM (#37493894) Journal

    I mean did you know many people have laptops that can take a 12.5mm tall HDD? But most people only buy a 9mm drive?

    So it would be nice if OCZ (or another manufacturer) could make a very thin (3mm) card that would piggyback on top of the HDD. It would also have to a SATA drive connector to attach it to the motherboard and then a loop through cable to attach to the drive. In this way the end user could add a SSD cache to their existing laptop!

    Is this feasible or am I missing something?

    • by hahn ( 101816 )

      I mean did you know many people have laptops that can take a 12.5mm tall HDD? But most people only buy a 9mm drive?

      So it would be nice if OCZ (or another manufacturer) could make a very thin (3mm) card that would piggyback on top of the HDD. It would also have to a SATA drive connector to attach it to the motherboard and then a loop through cable to attach to the drive. In this way the end user could add a SSD cache to their existing laptop!

      Is this feasible or am I missing something?

      Heat? Battery life?

  • And just how well does this extra level of complication recover from every kind of unexpected system shut down/BSOD/you name it in the consumer PC world?
  • It's called Smart Response Technology (SRT) and it was introduced by Intel as part of their Z68 chips.

    Granted, OCZ's version has a few more bells and whistles, but it's basically the same thing.

  • Anyone care to place bets on whether that DataPlex software is locked to only work with OCZ SSD hardware? Anyone care to bet on how long it will take before an open source equivalent appears on SourceForge and negates OCZ's proprietary stunt?

  • What is the advantage of using an SSD in this configuration? Granted, if the power went out, the SSD would retain the data versus a standard ram cache, but then again, the hard drive isn't spinning to accept the data. Also, SSDs tend to wear out in a few years, even with error correction. Now, most likely, the system would realize that and default back to the HD without the SSD, but again, a standard cache wouldn't have that problem, or at least not as soon.

    The only advantage I see is that an 128GB SSD is

    • by Arlet ( 29997 )

      The only advantage I see is that an 128GB SSD is a lot smaller than 128GB ram

      Also cheaper, lower power. and non-volatile. A battery wouldn't work, because DRAM needs to be refreshed, and with the size of the RAM, the current drain on the battery would be substantial.

  • I thought we decided that The Register was not a good source of news. Can we stop referring to it already?
  • Too bad OCZ's Vertex 3 line does nothing but blue screen and cause system freezes as well as not being detected by the BIOS on occasion. 9 firmware revisions since we bought them, installed in multiple computers, and still no fix. They won't be getting my business. Doesn't matter how fast it is if you can't rely on it.
    • Amen to that. Burned through 2 Vertex 3's in my latest build. Even went through some firmware battles.

      I had hope because I heard about how fast they were. They were fast - and I'll tell you what, they were also really fast to reboot every single time the machine blue screened, which was pretty often. Went with Crucial instead, and no problems since.

  • While the caching approach is slightly different, the idea is not new - I've had a Seagate Momentus XT in my MacBook for over a year now. It's a bearable price premium ($100 vs. about $60-70 for a typical 2.5" 500GB 7200 RPM drive) and there's definitely a performance difference.

    Best part: it's a single unit, so it'll work in a laptop. No additional software needed. You don't have to deal with OCZ's prices ($300-500 per the article)

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