7 Replies Latest reply: Jul 18, 2013 12:50 AM by Sammy Bogaert RSS

    Oracle on Windows - Storage Strategy

    Greg Sellek Newbie

      Hi everyone,

       

      We've recently been attempting to P2V our Oracle database server...the last physical server.  However, we're seeing some performance hits of up to 50% on the virtual system.  I know this is a very in-depth problem, and getting to the bottom of it would require lots more info here than I'm willing to subject you to.  However, I'd like to just simplify things and ask, "What's the best storage strategy for Oracle on Windows with Nimble?"


      We are a small shop and do not have a dedicated DBA, so it's important for us to KISS whenever possible.  Currently, the test system is simply using multiple VMDK volumes as multiple drives in Windows 2008R2 on VSphere 5.1 with multi-pathed 1Gbps iSCSI connections to the Nimble.  Would I really see a performance difference if we went to ASM volumes?  What about RDM?  If there was a difference, would it really make it worthwhile to lose the ease of administration of treating storage on this server similar to our other servers?

        • Re: Oracle on Windows - Storage Strategy
          Adventurer

          Hi Greg,

           

          I am an Oracle TME at Nimble Storage but by no means an expert on Windows or VMware.  From what you said, I would suggest setting up your Oracle database server as followed:

           

          1. Use VMDK for boot volume only

          2. Use guest direct attached storage for Oracle volumes

          3. Use multipath for Oracle volumes

          4. Create a striped NTFS volume for Oracle if possible

           

          You don't need to use ASM if you don't have a dedicated DBA.  Please let me know if you have any further questions.

           

          Thanks,

           

          Tom

            • Re: Oracle on Windows - Storage Strategy
              Greg Sellek Newbie

              Thanks for the reply Tom.  I'll stick to direct attached storage from the guest then.  One question though.  Why stripe the direct attached NTFS volumes?  I can see where this would be a benefit if the underlying storage was 2 separate LUNS, but it seems odd to do this with two separate volumes from the Nimble array.  I'm sure you know your array better than I do, so I'm just curious why you suggested this route.

               

              Thanks again,

              Greg

                • Re: Oracle on Windows - Storage Strategy
                  Justin Rich Adventurer

                  I cant see any reason you'd want to strip it. you cant do it from the nimble side and if you do it from the windows side you'll just add overhead with no value.

                   

                  I actually do a similar thing. We have our VM env on some HP chassis with Virtual Connect so its a tad more complex (with little advantage)

                   

                  Chassis.gif

              • Re: Oracle on Windows - Storage Strategy
                Ted Joffs Newbie

                I am sorry, but there is almost no perceptible difference between RDMs and VMDK based storage that is DEDICATED.  (see here: vSphere 5.1 – VMDK versus RDM | VMware vSphere Blog - VMware Blogs)  What I would suggest is this:

                 

                1. Can use a SHARED Datastore for the boot drive.
                2. Use DEDICATED datastores and create a single VMDK volume on the datastore for the Oracle volumes.
                3. Multi-path is always better, generally speaking.

                 

                This will give you the benefits of the VMDK Encapsulation for easy management, movement, re-sizing, etc. and will also give you the only real benefit of RDM; dedicated disk.

                 

                TKJ

                  • Re: Oracle on Windows - Storage Strategy
                    Justin Rich Adventurer

                    well is that to say there is no difference in the performance policies in nimble? part of the reason for doing the separate disks is that reason, however i dont know what the actual value is in the different perf policies.

                      • Re: Oracle on Windows - Storage Strategy
                        Ted Joffs Newbie

                        No.  That is actually a good point.  The performance policies could have an impact here.  Generally speaking, the difference would be imperceptible on like for like disk. I have a Nimble in the lab that I can take a look at later to see what the performance policy differences are for Oracle vs. VMWare to be sure, but my thinking is that you could probably set the performance policy for those dedicated datastores to match the Oracle policy you would use for the RDM to take advantage of it as long as they did not change the block sizes, etc.  Good point.

                          • Re: Oracle on Windows - Storage Strategy
                            Sammy Bogaert Wayfarer

                            I had the same discussing with Nimble but on Exchange.  We have Exchange volumes in a dedicated VMFS volume.  As long as you ONLY put that VMDK in that volume, it is indeed recommended to set the Performance Policy to Exchange/Oracle/SQL/... and NOT to VMware.

                             

                            Make sure to put other stuff like your boot VMDK on a datastore with the ESX performance policy!