3 Replies Latest reply on Mar 13, 2014 7:05 AM by Noel Carboni

    OT: A Hardware Question

    Trevor.Dennis Adobe Community Professional

      Testerday I suffered a major system failure.  It started with a RAW file opening in ACR and after a moment, the image area became a noisy white.  All images were doing the same, and when I loaded one into Photoshop CC, it is was still white, and then the system crashed BIG TIME.


      I was not able to reboot without eventually agreeing to use Start Up Repair tool.  This despite waiting for over an hour for the hung Windows start up screen to sort itself out.  When it did load, both my raid0 arrays were missing. After more restarts I got both arrays showed, but I could only access one of them, so I decided it was time to reinstall Windows.


      After some of the discussions we've had here, and the good experience I have my laptop that has the OS on a pair of SSDs in a raid0, and especially thinking about Noels monster boot drive, it seemed too good an opportunity to pass up, so I ordered a pair of Samsung 250Gb EVO SSDs.


      But I had some questions about when to load the Intel raid driver during the Windows install, so started this thread on the PremPro Hardware forum.  They really know their stuff over there, and helped me loads when I built my box over two years ago.




      The first point that was made to me was that the EVO drives are not designed to work in a raid array, so after some frantic phone calls, and another NZ$145 I was able to change the order to a pair of Samsung 256Gb Pro SSDs.  There is information about EVO vs Pro in this thread, but it doesn't really say why the EVO is pants




      After some Googling I answered my own question about when to install the Intel raid driver during Windows Install, but then Bill Gehrke knocked me flat on my backside saying that the world will come to an end if I use a raid0 for my boot drive.


      Anyone here got thoughts on this?  Especially Noel who has a four or six SSD raid0 that he uses for everything.  As I mentioned in the PremPro Hardware thread, I use Shadow Protect, and while I have not previously used its boot drive image feature, I could do.


      A stupid question regards my CC subscription.  I assume I just need to Quit the CC Desktop Application Manager let Adobe know I am 'deactivating' the current installation ready for the new one? Yes I know I should go read the FAQ I answer similar questions with on this forum.


      Anyway...  It will be nice to have a clean install of Win 7 Pro, as it has been getting just a wee bit sick, and is definitely less snappy than when first buit and installed.  And I _really_ want to use those 256Gb Pros for the boot drive.  I am committed to getting them now.


      [EDIT]  It would be nice to say I lost nothing, but I have lost a bigish project that was being accessed from a drive not covered by Shadow protect.  This was down to pure lazyness.  I got another 4Tb USB3 external to back up my back ups, and empty the two raid0 arrays so I could start again with the drive set up with Windows.  That brings me up to 18Tb, so no excuses with my back up strategy now.

        • 1. Re: OT: A Hardware Question
          Noel Carboni Level 8

          Hi Trevor,


          Sorry to hear about your data loss.



          Trevor Dennis wrote:


          Bill Gehrke knocked me flat on my backside saying that the world will come to an end if I use a raid0 for my boot drive.


          That's simply rubbish (coming from one who's booted from a RAID 0 array of SSDs since 2 years ago - then Win 7 and now Win 8.1).  I didn't go elsewhere to read about that...  Did he say why he felt that way?


          I can only guess that these kinds of comments come because what works best nowadays didn't really work just a few short years ago, and old rules of thumb die hard.


          I do think you made the right choice moving up from the EVO to the Pro drives, though I have actually heard of folks using EVOs in RAID (you probably didn't want to hear that).  You'll get better performance from the Pro drives, which have better internal controllers.  Possibly more longevity as well.  What's the MTBF on those drives?  2 million hours (mine are)?  Even RAIDed together, they're likely a LOT more reliable than a single spinning hard drive.


          There's a reasonable chance you won't need to load a special driver into Windows at all, assuming you're going to be creating your RAID array using your Intel OROM (BIOS).  Windows now does know something about these kinds of operations.  If you build the array in the BIOS, then go to install Windows and it sees the composite drive and offers to install on it you're there.  If not, you'll need a driver.  If Windows is willing to install on it, it's also happy to back it up, restore it, do shadow copies on it, etc.


          I don't maintain quite the number of terabytes you do, but I do make nightly system image backups, which by virtue of the fact that everything I use from day to day - including my OS, apps, data, photo library, etc. - are on my C: volume, everything's protected.  I do have some other data on spinning hard drives in my system for low access data, and I back that up separately as well.


          I have never seen a computer as powerful and responsive as the one I currently have - and a great deal of that responsiveness is because of the SSD drive array.  Everything's instantaneous.  Okay, not Photoshop, but it cold starts in only 2.4 seconds.  You will likely see better than that, as SSD controllers have gotten a good bit faster in the last 2 years.  Samsung 840 Pro drives are pretty near cutting edge.


          Only thing is you didn't get enough of them. 



          • 2. Re: OT: A Hardware Question
            Trevor.Dennis Adobe Community Professional

            Thanks for taking the time Noel.  I know how busy you are right now.


            Apparently there are two firmly entrenched camps regarding using a raid array as your boot drive, and AFAICT the arguments against are that drive repair utilitys don't work on raid arrays.


            I've had an error on boot indication for ages on one of the WD Blacks in my Exports raid0.  I asked on the PPHF and was told by Erik (I think) that the only way to fix it would be to remove the data and unraid it so I could Smart scan it or similar.  That would map the bad sectors so I could raid it again.   ISTM that I would not have two identical drives after that, so I didn't like to risk it.


            I am going to go ahead with the raid0 using the two 256Gb Pro SSDs.  I had an email a while ago saying they are on ther way, and I have worked out how and when to install the driver, (you choose the Custom Advanced option near the start of the Windows installation, and go to Drive options and Install driver).  I had all sorts of trouble when setting things up when this system was first built, and the Intel Enterprise driver fixed the problems at a stroke.  That info also came from the PPHF, and some of the guys over there can be a wee bit terse so you just tend to get a short answer, and rarely any details.  I guess I have posted my share of short swift replies so fair dos.


            BTW  I have now spent >NZ$2700 on computer components in the last couple of months, and the Pros are a lot more expensive than the EVO drives.  I am also flat out of SATA headers on my Z79-UD5 so I'll need a decent controler card before I can expand further.  Bill tested a pair of 256Gb Pros at better than 1000Mb/s which is ten times better than the rubbish Toshiba I am currently using, so that's going to do me for now.



            • 3. Re: OT: A Hardware Question
              Noel Carboni Level 8

              RAID very nearly adds up the performance of the member drives, and with near-zero latency (as compared to huge seek times in electromechanical drives), there's very little performance downside to RAIDing SSDs as compared to HDDs.


              Once you exceed 1 gigabyte / second speeds, which as you say leave even RAIDs of HDDs in the dust, other factors start to come into play.  The actual latency introduced by the basic components in your system, measured in microseconds - not milliseconds, start to limit the practical speeds of every day I/O operations.


              Benchmarks like the one above show the raw performance of a gargantuan single read or write, but your system almost never does I/O of that size.  The holy grail of those really "in the know" about RAIDing SSDs is something called "4K speed".  That is, how fast can your I/O subsystem turn around requests for chunks of data in tiny, 4 kByte chunks - the kind of I/O you most often really do.  It turns out the Intel chipset provides some of the lowest-latency, most direct I/O there is.  Those in the know say always choose Intel-controlled SATA ports - never use Marvell-controlled SATA ports, even if the advertised speed seems faster.


              My own 4K I/Os measure about 125 megabytes/second throughput, which is slow by today's standards.  I've seen benchmarks from systems whose 4K I/Os are now nearing 1 gigabyte / second.  That threshold may have been crossed only recently.  THAT is a system whose responsiveness will second to none.


              By the way, the 4K I/O speed of a typical HDD is not even in the same ballpark, primarily because of on-drive cache.  Real throughput in extended operations (i.e., when the disk gets to really being hammered for a long time, such as during Photoshop swapping) is even worse!





              P.S., I have an 8 port PCIe SATA III controller called a HighPoint 2720SGL.  I'm sure HighPoint has more powerful cards now than they had 2 years ago.