6 Replies Latest reply on Feb 20, 2019 12:00 AM by breacH

    Slow transfer rate between datastores (copy or move)

    breacH Lurker

      Hello,

       

      I just did a fresh install of ESXI 6.7 on my home lab server. (i7 2600 on intel motherboard)
      The VMs are running fine, all stored on SSD.

       

      I wanted to make a backup of the VMs from the SSD on a WD 1TB drive and the transfer is extremely slow.
      For example, a Windows 10 VM thin provisioned that use actually about 30 GB took more than 2 hours.
      I did the copy with the datastore management.

       

      Is that any normal?

       

      I remember on ESXI 5.5 the transfer was way more quicker.

       

       

      Exact setup is:
      - intel i7 2600
      - motherboard intel DZ77GA-70K

      - Samsung 860 EVO SSD and WD Blue 1To (both VMFS 6)
      - Both drives connected to the same sata controller (intel one)

       

       

      Thanks a lot for the help, and have a nice day!

        • 1. Re: Slow transfer rate between datastores (copy or move)
          bhuqwl Novice

          Have you tried a smaller VM? Are average transmission rates all slow?

          • 2. Re: Slow transfer rate between datastores (copy or move)
            breacH Lurker

            Thanks for your reply.

             

            Yes, all transfer are slow between datastores, whatever the VM's size.

             

            But i noticed that uploading or download on datastores from desktop PC is good (~110MB/s)
            Makes it even stranger..

            • 3. Re: Slow transfer rate between datastores (copy or move)
              breacH Lurker

              Hello,

               

              A little bump of this thread..

               

              I saw in the vmk warning log something like:
              "ScsiDeviceIO: 1199: bla bla sata device :Deviceperformance has deteriorated. I/O latency increased value etc"

               

              This line repeats several times with latency always bigger, and then:

               

              "NMP: nmp_DeviceRequestFastDeviceProbe:237: NMP device bla bla sata device state in doubt; requested fast path state update..."

               

               

              I dont know if this could be related to my problem.

               

              I also read that the native vmw_ahci driver sometimes causes problems.

               

              Should i switch to the legacy linux driver?

               

              I'm a bit afraid to make this move...

               

               

               

              Thanks again for your replies!

              • 4. Re: Slow transfer rate between datastores (copy or move)
                breacH Lurker

                Hi,

                 

                Thread bump again..

                Just to say that i tried to disable the native esxi driver and let the legacy one to load.

                 

                No change in speed in datastore or between datastores.

                 

                I give up on this

                • 5. Re: Slow transfer rate between datastores (copy or move)
                  wila Guru
                  Community WarriorsvExpertUser Moderators

                  Hi,

                   

                  Not exactly sure what this means:

                  I did the copy with the datastore management.

                   

                  But FWIW, after reading this thread I suspect that the WD Blue disk is not performing well in your config.

                   

                  --

                  Wil

                  | Author of Vimalin. The virtual machine Backup app for VMware Desktop Products
                  | Vimalin : Automated backups for VMware Fusion and VMware Workstation Professional
                  | More info at https://www.vimalin.com
                  | Twitter @wilva
                  | VMware Wiki at http://www.vi-toolkit.com
                  • 6. Re: Slow transfer rate between datastores (copy or move)
                    breacH Lurker

                    Hi,

                     

                    Sorry for late answer..

                     

                     

                    I meant to copy file with the datastore's files manager. The one on the web interface.

                     

                    The WD Blue disk is old but functionnal. No SMART error or anything.

                     

                    I did installed GhettoVCB and made a script to backup all the VM.
                    With GhettoVCB it copy at a constant 96MB/s which is pretty good.

                     

                    I think that when i do copy VM with the datastore's file manager, the system inflates VMDK files, hence the slow rate and long time copy.

                     

                    Thanks again for your replies and have a nice day!