Very slow file transfer from hyper-v to host drive

cereberus · 29 Mar 2017

Kari said:

This is still the fastest way to copy from Hyper-V vm to host:

Attachment 127142

In elevated command prompt, assign drive ID for a host share and copy.

Thanks - I will try this. Actually, I discovered slow file copying from Hyper-V to host was not the issue. There is something wrong with my Host install that craps out when I try to copy the folders with all the UUP files. I would try a repair upgrade but with CU round the corner, I will wait.

As you will probably remember (;-)) my host OS is PRO N, so I do not have a 15063 iso as (is this still true in fact?) N Insider versions do not exist.

I also have a PRO dual boot with 15063, and I will see if that works OK.

jimbo45 · 30 Mar 2017

Hi folks --

Not an answer to the above thread - but just added here purely for information

Those of you using VMWARE with Windows HOSTS and VM's - you can achieve speeds of 300 Mb/s or faster by using Storage spaces on the HDD you want to share and simply share it with the VM.

Of course if your share is via wifi then the speed will drop considerably depending on the speed and quality of the wifi.

If you are using connection via a "Virtual ethernet adapter" this should be capable of 1 - 10 Gib/s and so will be fast enough.

For really large folders / files say data drives > 2 TB the Windows NTFS standard file system isn't really good enough any more - Storage spaces work brilliantly. I think these can be used also with HYPER-V.

@Kari on that one though.

Cheers
jimbo

Kari · 15 Apr 2017

I don't know what's happened, if it's build 16176 or something else, but I cannot complain anymore about the transfer speed between Hyper-V host and virtual machines.

This is what I get when using net use X: \\HostName\SharedFolder in elevated Command Prompt on VM to set direct network access from VM to a host share, then copying ISO file created on VM with UUPtoISO to host:

Very slow file transfer from hyper-v to host drive-image.png

I get the same 750 Mbps to 1,000 Mbps from host to VM simply by creating a share on VM, adding it on host in elevated Command Prompt with net use, and using copy / xcopy / robocopy to transfer files instead of File Explorer> Network.