6 Replies Latest reply on Dec 2, 2019 8:15 AM by louyo

    Very poor SSD performance inside Windows 10 guest running on VMWare Workstation on a Windows 10 host

    roblevine Novice

      Hi all,

       

      I'm seeing very poor SSD performance on my Windows 10 guests (not that I've benchmarked any other guest OS's) running on Windows 10 hosts.

       

      This is happening on both my Desktop workstation and my laptop.

       

      I'll give more details of the laptop scenario.

      Host: Dell XPS15 9560 with a 512GB SSD and 16GB RAM, running Windows 10 1803.

      Guest: VMWare workstation hardware compatibility 14, 4GB Memory allocated, 1 processor, 4 cores, VT-x/EPT enabled. Running Windows 10 1803.

      No snapshots, all disks compacted/defraged.

       

      As detailed below, performance is pretty dire - especially when you look at the non-sequential tests. Performance is a factor of 4-7 times slower than on the host. I've been using Workstation for years and expect some performance drop within a guest, but not on this scale. It is bad enough that it seriously impacts Windows performance and usage.

       

      I've tried experimenting with different disk types (NVMe/SCSI, pre-allocation/lazy provisioned) - none make a significant difference.

      The performance is similar with antivirus disabled on both host and guest (Windows Defender on both)

       

      Does anyone have any ideas for resolving this, or investigating the cause? Might this be a performance bug in Workstation itself?

       

      All help gratefully received.

       

      Host disk performance is good:

      CrystalDiskMark-Host.png

       

      Guest performance is poor:

       

      12GB SCSI, pre-allocated, single file:

      Guest-12GB-SCSI-PreAlloc.png

       

      14GB NVMe, pre-allocated, single file:

       

      Guest-14GB-NVMe-PreAlloc.png