Optane 4K performance halved within Hyper-V clients RRS feed

  • Question

  • I got a question about SSD performance of Hyper-V clients.

    I used an Intel 900P 280GB drive as the storage for two Hyper-V clients, both running Windows 10 Enterprise 1809. If I only power one of them on, and I use CrystalDiskMark 6 to test the disk performance, the Q1T1@4K (Queue 1 Thread 1@4K) result (the one that made all the difference with Optane) will be only Read:110MB/S Write:105MB/S, but if I test the same drive in the host system, the result will be Read:235MB/S Write:225MB/S.

    I tried different platform, and the result is identical, the disk performance of clients are seemingly limited at 110MB/S.

    I managed to set up the entire 280GB drive to direct pass through as a SCSI drive for one client, and the disk performance is still like above, halved the test result within host system.

    The sequential read and write performance is the same for clients and the host, but that does not make the biggest impact on the smoothness of the system. I wonder if there are some tweaks to change this.

    My host system configuration is: AMD Ryzen 2600, 8-core, 64GB DDR4 2666Mhz, Intel 900P 280G NVME

    • Edited by VentLe Wednesday, November 20, 2019 7:06 AM
    Monday, November 18, 2019 6:33 AM


All replies

  • "My host system configuration is: AMD Ryzen 2600"

    The AMD Ryzen chip is not certified to run the Windows Server/Hyper-V Server operating system (  Though the chip may be able to run the Server OS, it has not been tested to be consistent across workloads.  Without AMD support for the chip, it ends up leaving end users with the responsibility to find the cause of any anomaly in performance.  Your hope in posting in a forum like this is that someone else may have run into a similar issue with a similar configuration.  Otherwise, there are no guarantees when running on an unsupported chip.


    Monday, November 18, 2019 1:47 PM
  • Thanks for the comment! 

    This is a test lab I play with at home. I was not aware of AMD not supporting the Ryzen chip to be used in Server OS. Well, before this, I used the same storage with an Intel Xeon E3-1230 V2, which is a certified CPU for Server OS, but the 4K performance was still halved in Hyper-V clients.

    My hope when posting this was to find out if there is anyone seeing a much higher 4K performance in Hyper-V clients. I am not sure if it is the CPU or the OS that has caused this limit of performance output.

    • Edited by VentLe Tuesday, November 19, 2019 3:10 AM
    Tuesday, November 19, 2019 3:08 AM
  • Tuesday, November 19, 2019 6:19 AM
  • As Frank's reply metioned on your shown post, we have no optane to test, to help you better, you could consult it in Intel forum for better answer.

    Thanks for your understanding!

    Best Regards,


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    • Marked as answer by VentLe Wednesday, November 20, 2019 6:52 AM
    Tuesday, November 19, 2019 8:47 AM
  • Maybe it is the Optane.  It is not uncommon for certain devices to not be recognized properly without a chipset driver installation.  As the Ryzen is not supported for Server OS, I question that AMD has written a chipset driver for Windows Server.  As a result, the Optane might be getting recognized for optimal use.  That's a discussion that needs to taken up with AMD.


    Tuesday, November 19, 2019 1:54 PM
  • AMD is a false flag.  OP had same performance hit with an Intel Xeon based system.
    Wednesday, November 20, 2019 12:59 AM
  • Thank you so much for pointing that out! It seems to be irrelevant which CPU is being used, the 4K Q1T1 performance will always be halved inside Hyper-V clients. 

    BTW, I am using evaluation edition of Windows Server 2019 and Windows 10 Enterprise. I am not sure if that makes any difference, although that to me is unlikely.

    Wednesday, November 20, 2019 6:50 AM