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Are SSD Accelerators Any Good?

Posted by Soulskill on from the newton's-second-law-objects dept.

MrSeb writes "When solid-state drives first broke into the consumer market, there were those who predicted the new storage format would supplant hard drives in a matter of years thanks to radically improved performance. In reality, the shift from hard drives (HDDs) to SSDs has thus far been confined to the upper end of the PC market. For cost-conscious buyers and OEMs, the higher performance they offer is still too expensive and the total capacity is insufficient. SSD cache drives have emerged as a means of addressing this situation. They are small, typically containing between 20-60GB of NAND flash and are paired with a standard hard drive. Once installed, drivers monitor which applications and files are accessed most often, then cache those files on the SSD. It can take the software 1-2 runs to start caching data, but once this process is complete, future access and boot times are significantly enhanced. This article compares the effect of SSD cache solutions — Intel Smart Response Technology, and Nvelo Dataplex — on the performance of a VelociRaptor, and a slow WD Caviar drive. The results are surprisingly positive."

8 of 331 comments (clear)

  1. bcache by Anonymous Coward · · Score: 5, Informative

    For Linux users: http://bcache.evilpiepirate.org/

    Lets you use any SSD as a cache in front of another filesystem.

    1. Re:bcache by ShoulderOfOrion · · Score: 5, Interesting

      Why bother? I have an HDD mounted as /, and an SSD mounted as /usr on my Gentoo system. Using atop I consistently see the HDD receive 10-20 times the writes the SSD receives but only about 2x the reads. In other words, on Linux the SSD is already serving primarily as a read-only caching filesystem just by mounting it correctly.

    2. Re:bcache by Gaygirlie · · Score: 5, Informative

      You should not expect much speedup from using a 10Mbyte/s memory card in front of a standard 150 MByte/s sustained transfer drive.

      You said it yourself: "sustained." The whole point with ReadyBoost is that it uses these Flash-devices for matters where low latency is more important, sustained transfer-rate is therefore not important. It doesn't even try to cache multi-megabyte files, it caches small files and details that are accessed frequently: a regular HDD is quite bad at reading dozens of small files from all over the disk due to seek times.

      If the small files are stored in your cache, you might save some seek time. But you can't compare some ultra-slow USB / SDHC card to a 2-300 Mbyte/s SSD.

      That's what I said.

      I tried the SDHC, did not work well. A fast USB 3.0 stick in a USB 2.0 port was way better, but still does not compare to SSD.

      If you were expecting SSD-level performance then you clearly didn't understand fully what you were doing in the first place. It is not meant to replace an SSD, it is simply meant to speed up your system as compared to only using a regular HDD.

  2. No. by Anonymous Coward · · Score: 5, Insightful

    Hybrid drives or mixed mode setups kinda suck ass now that actual ss drives are getting to a reasonable price/size.

    SSD for os/programs.

    Giant TB+ drive for storage and media files.

    1. Re:No. by wbr1 · · Score: 5, Insightful

      For the average joe, they dont want to have to manage putting os/apps/frequent files on one drive and split the rest elsewhere. Software that automagically does this and keeps the cache up to date is a boon for the non power user.

      --
      Silence is a state of mime.
  3. Re:I have seen SSDs used just to load the OS by pla · · Score: 5, Informative

    To me it is not worth it to watch your os boot faster.

    First of all, putting the OS on a disk by itself doesn't only mean that Windows runs faster - The OS reads and writes to its files on a near continuous basis. For years before SSDs, we've known that simply getting that activity segregated onto its own disk, away from "real" file activity, gives a decent performance boost across the board; moving it to an ultra-fast random-access media helps even more (and even if you don't care about boot time, how about "responsiveness"? Every time Windows needs to wait for some stupid little icon to load, you need to wait for Windows to wait for some stupid little icon to load).

    Second, SSDs have gotten a lot bigger and a lot cheaper. You no longer need to decide between spending a fortune or segregating your apps out; a $60 SSD will hold the OS and every app you could ever possibly run, with plenty of room to spare. Yes, you'll still want that second big-slow-and-cheap HDD for general purpose storage, but you haven't needed to carefully weigh "on which disk should I install this program" for at least a year.


    Flash ram is not a permanent solution and will die due to the limited number of writes.

    And you think a drive with actual moving parts will live forever?


    Make no mistake, SSDs have their flaws, and cost definitely still counts as one of them. But once you really use a system set up with SSD system / HDD data, you'll never even consider going back. And mere boot time has nothing to do with it.

  4. Re:I have seen SSDs used just to load the OS by cdrudge · · Score: 5, Informative

    What also is not addressed in the article is the reliability of the SSDs. Flash ram is not a permanent solution and will die due to the limited number of writes. If you use mysql or MS access or run low on space and use XP that thing will be dead in a matter of months. It can only handle so much paging and writes before it dies. Tricks in the firmware move the write bits to random places in memory to prevent this but as it fills up the paging needs to keep to keep hiting the same memory addresses.

    There are a variety of different ongoing tests to look at how long drives actually last. Looking at a fairly standard older Intel 320 40GB drive, it went 190TB written before the MWI threshold was reached, and continued on until 685TB. That means it completely rewrote the drive 17500+ times.

    No, it won't last forever. And it's not ideally suited for every single industry and use. But for the typical user, they are more likely to need a larger drive or otherwise upgrade then wear out the drive.

  5. Re:Single Article - Multiple Pages by sortius_nod · · Score: 5, Informative

    Not only this, the claims are at least 12 months out of date. SSD's are now less than $1/GB, & the average drive sold now is 120 or 128GB.

    I upgraded my desktop with a cheap solution (AMD A8, 990FX, 16GB RAM, 128GB SSD, 2TB HDD) all for less than my last upgrade cost ($669 vs $955) 3 years ago. SSDs are definitely part of the norm now, we order many machines with dual 128MB SSDs in them, both laptops & desktops. The price difference is negligible, so this article seems more like a cry by someone attempting to hold onto the old way of doing things.