22 Replies Latest reply on Jan 15, 2013 3:32 PM by Alex - DV411

    External SATA raid performance

    Jon-M-Spear Level 4

      Can anybody tell me what a good average transfer/write speed should be from a Win 7 64 PC to an eSATA RAID0 device that shows 185 MB/S write speed in Blackmagic's speed test.

       

      When I transfer 130 GB of XDcam data across to a 1TB G-Raid device that has no previous data on it, the speed stars out at about 120 MB/s and gradually slows until it maintains 20-24 MB/s for the majority of the transfer.

       

      Should I be expecting higher transfer rates than that?

       

      Thanks.

        • 1. Re: External SATA raid performance
          Harm Millaard Level 7

          My gut feeling is yes, you should expect better transfer rates. 20 - 24 MB/s is about equal to USB2. But a lot depends on the controller in that G-Raid box. eSATA is always way slower than a SFF-8088 connection to an internal raid controller, but this slow? I would expect a sustained transfer rate of at least 120 MB/s.

          • 2. Re: External SATA raid performance
            Bill Gehrke Adobe Community Professional & MVP

            Jon, that is lousy, I do not know your RAID configuration, but one good internal drive would do much better than that 20-24 MB/sec!  Here are my Read and Write benchmarks on a single SATA3 Seagate 7200.14 2 TB drive with HD Tune Pro (all with my Areca 1880).  Sorry I do not have the Blackmagic test while a good end to end test it does not tell you if it is a read or write problem

             

            HD-Tune-2-GB-SATA3-read.jpg

            HD-Tune-2-GB-SATA3-write.jpg

            Here are four of them in SATA3 RAID 10

             

            HD-Tune-4x2TB-RAID-10-Read.jpg

            • 3. Re: External SATA raid performance
              ECBowen Most Valuable Participant

              The transfer rate changing like that is a firmware issue on the controller that is allowing Win 7 to throttle the bandwidth. Win 7 will throttle the bandwidth considerably on removable devices to ensure safe data transfer incase the drive disconnects. Often times even setting the drive caching policy to performance instead of safe removal wont work because the Firmware on the controller does not support that with Win 7 and the device still functions under the safe removal policy. Check and see if you have a driver and firmware update for the controller. Then see if that fixes the caching policy for the E-Sata drives.

               

              Eric

              ADK

              • 4. Re: External SATA raid performance
                Jon-M-Spear Level 4

                Thanks chaps.  I clearly need to investigate further.

                 

                Jon.

                • 5. Re: External SATA raid performance
                  Jon-M-Spear Level 4

                  ...My old Lacie 2Big Quadra seems to be chugging away at a sustained 133 MB/s on the same PC.

                   

                  Something's clearly wrong with the G-Raid mini with its 22 MB/s!

                  • 6. Re: External SATA raid performance
                    ECBowen Most Valuable Participant

                    Likely the Lacie does not support the Win 7 Throttling like the G-Raid does. I highly recommend you look for a firmware/driver update for the controller. I have seen this many times with E-Sata and the resolution has always been the same.

                     

                    Eric

                    ADK

                    • 7. Re: External SATA raid performance
                      Jon-M-Spear Level 4

                      Thanks Eric.

                       

                      Throttling is a new one on me.  I'm not sure I know its purpose.

                       

                      I can understand that my Dell Precision T3500 may have an out-of-date driver, although I do update regularly.  However, my M6600 has, this very week, been rebuilt after a raid drive failure, and the Dell bloke remotely installed the current drivers.

                       

                      There does seem to be a lot of internet chatter about the poor transfer rates of the G-Raid Mini but, unfortunately, not many solutions.

                      • 8. Re: External SATA raid performance
                        JEShort01 Level 4

                        Jon,

                         

                        I have a G-RAID mini and the slowest transfer rate just over 100MB/sec for reads and writes as per HD Tune Pro (2MB block size):

                         

                        G-RAID mini read.jpg

                         

                        G-RAID mini write.jpg

                         

                        Have you checked your drive hardware / properties / Policies settings to make sure they are set for fastest performance (write-caching policy on, etc.).

                         

                        Jim

                        • 9. Re: External SATA raid performance
                          Jon-M-Spear Level 4

                          I have set the policies to performance etc.

                           

                          I have now compared USB2 with eSata.  USB2 is slightly faster @ 24 MB/s - so somethig's definitely askew.

                           

                          Just to be clear:  When I test it using the Blackmagic speed test, it reports a write transfer of between 125 - 135 MB/s.

                           

                          It's when I actually transfer a (120Gb) file to it via eSata that Windows 7 tells me it's 22 MB/s, compared to about 135 MB/s of the Lacie.

                          • 10. Re: External SATA raid performance
                            Bill Gehrke Adobe Community Professional & MVP

                            In addition to Jim's suggest to you, have you turned off indexing and I hope you did not turn on compression! 

                            • 11. Re: External SATA raid performance
                              Jon-M-Spear Level 4

                              Bill, nothing is indexed or compressed.

                              • 12. Re: External SATA raid performance
                                Jon-M-Spear Level 4

                                ...Interestingly (for me, anyway), it's read speed, ie, transferring from the G-Raid to the M6600 internal raid is a pretty constant 117 MB/s.

                                • 13. Re: External SATA raid performance
                                  ECBowen Most Valuable Participant

                                  Throttling means Win 7 purposefully slows down the data sent to the drive to ensure the data is written successfully incase there is a power interruption. The Caching the controller normally uses as your seeing on Read operations is not being utilized on write operations for safe data transfer. This was a feature Win 7 really brought to the table that many were not aware of. However this severely lowers the write speed to that drive while the caching policy is in that mode. There is a caching policy option in Win 7 to change that to performance however some controllers firmware do not recognize that change. That is why a firmware update is required when that happens. Specific firmware version often require specific Driver versions. So you need to make sure you have the updated firmware and driver for the controller. This is also the reason the read speed is normal and the write speed is slow. That is the symptom for this problem.

                                   

                                  Eric

                                  ADK

                                  1 person found this helpful
                                  • 14. Re: External SATA raid performance
                                    Jon-M-Spear Level 4

                                    Thanks.

                                     

                                    I spoke with a TS support geezer at G-technology yesterday. He asked me to defer to email because he hadn't a clue! 

                                     

                                    I haven't had a reply yet.   I will put your explanation to them once they do.

                                    • 15. Re: External SATA raid performance
                                      Jon-M-Spear Level 4

                                      I'm now on my third G-Raid Mini.  Each one that G-Tech sends me behaves in exactly the same way - ie p*** poor write speeds of about 20 MB/s. 

                                       

                                      However, a recently acquired G-Raid 4TB in raid-0 behaves as expected with read/write speeds of around 180 MB/s.

                                      • 16. Re: External SATA raid performance
                                        Jon-M-Spear Level 4

                                        I am now on my 6th G-Raid Mini 1Tb. G-Technology has even apparently tailormade the eSata controller for me on this latest replacement.  However, there is absolutely no change: the sustained write speed remains at about 20 Mb/s, making it unsuitable for acquiring live camera with 50Mb/s streams.

                                         

                                        By way of recompense, I was given a 500Mb, 5400rpm G-Raid Mini.  Oddly this one writes at a sustained rate of 55MB/s.

                                         

                                        Has anyone in the 6 months since I stared this post experienced similar performance issues?

                                        • 17. Re: External SATA raid performance
                                          ECBowen Most Valuable Participant

                                          As i stated above Jon, If the firmware for the controller is not updated with the driver, this issue will not go away. That is why you have had so many of these show the same problem. What E-Sata controller do you have now. Did they tell you what Storage controller they use on the G-Raid and did they ever try a firmware update for it?

                                           

                                          Eric

                                          ADK

                                          • 18. Re: External SATA raid performance
                                            RjL190365 Level 4

                                            Jon-M-Spear wrote:

                                             

                                            I am now on my 6th G-Raid Mini 1Tb. G-Technology has even apparently tailormade the eSata controller for me on this latest replacement.  However, there is absolutely no change: the sustained write speed remains at about 20 Mb/s, making it unsuitable for acquiring live camera with 50Mb/s streams.

                                            You are also confusing megabits per second with megabytes per second. 50 Mb/s (actually, 50 Mbps) video streams actually have an average transfer rate of only 6.25 MB/s, which is still within the 20 MB/s reported transfer rate of your G-RAID Mini. However, the 20 MB/s reported rate is still far below what the disks themselves are physically capable of.

                                            • 19. Re: External SATA raid performance
                                              Jon-M-Spear Level 4

                                              Eric, G-technology have been proactive on this issue and are aware if the issues.  They have apparently updated / adapted the on board controller / firmware - to no avail. 

                                               

                                              Dell won't take responsibility and tells me that all drivers on my T3500 and M6600 are up-to-date. In fairness, there are no updated drivers available on its website.

                                               

                                              RjL190365, that's a very fair point, and one that's been completely misinterpreted by myself and G-Technology for months!  Thanks for pointing it out.  However, benchmarking aside, in real world situations, the G-Raid Mini 1Tb was not reliably capable of acquiring 50 Mbps streams for sustained periods (90 minutes is so).

                                               

                                              I will now try the 500Gb 5400 Raid0 that I was given, as it appears to perform better than the 1Tb 7200 Raid0.

                                              • 20. Re: External SATA raid performance
                                                Bill Gehrke Adobe Community Professional & MVP

                                                Jon-M-Spear wrote:

                                                 


                                                Dell won't take responsibility and tells me that all drivers on my T3500 and M6600 are up-to-date. In fairness, there are no updated drivers available on its website.

                                                Big mistake, You would be better off going to the manufacturers web site for the real up to date drivers.

                                                Jon-M-Spear wrote:

                                                 

                                                However, benchmarking aside, in real world situations, the G-Raid Mini 1Tb was not reliably capable of acquiring 50 Mbps streams for sustained periods (90 minutes is so).

                                                 

                                                That sounds to me like you have interfering processes going on.  Have you turned off indexing and anti: virus, spam, malware etc when you try this?

                                                • 21. Re: External SATA raid performance
                                                  Jon-M-Spear Level 4

                                                  Bill, good point about not relying on Dell.

                                                   

                                                  Regarding interferring processes, my eSata Lacie Raids and G-Raid (not mini!)  all behave to spec, so it appears to be specific to the G-Raid Mini 1TB and, to a lesser extent, the Mini 500Gb.

                                                  • 22. Re: External SATA raid performance
                                                    Alex - DV411 Level 2

                                                    Bill Gehrke wrote:

                                                     

                                                    Big mistake, You would be better off going to the manufacturers web site for the real up to date drivers.

                                                    It's often a big mistake not to, if one expects to be well supported by Dell.  Depends on the situation.