KVM/XEN Simlutaneous CPU Passthrough on same cores


Recommended Posts

So I accidentally had CPU host passthrough AND emulated QEMU64 running on the same cores.  I had believe that passthrough was like locking the guest to those cores physically.  However after thinking about it for a bit, i thought maybe emulated was more around getting a reduced but more consistent set of CPU extensions so that virtual machines can be live migrated.

 

So if host passthrough allows more CPU extensions to be passed through (and it does), is there anything stopping me from running all my VM's in host passthrough mode even if they touch the same cores simultaneously?

 

Does anyone have a definitive answer?  I'm still googling, but haven't come up with anything yet.

 

Many thanks,

 

Marshalleq

Link to comment
16 hours ago, Marshalleq said:

So if host passthrough allows more CPU extensions to be passed through (and it does), is there anything stopping me from running all my VM's in host passthrough mode even if they touch the same cores simultaneously?

no, you can stack as many vm's on a core as you want but will pay a penalty in performance and latency.

 

 

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.