Faster Live Migration–Which Option Should You Choose?

Okay, now that I have talked about faster live migration with compression and faster live migration with RDMA – one of the first questions that comes to mind is: which option is right for you?

When we were developing Hyper-V in Windows Server 2012 R2 we did a lot of testing to try and come up with an answer to this question – and the answer is surprisingly simple.  All you need to know is: how much network bandwidth do you have available for live migration?

If it is 10gbit or less – use live migration with compression.

If it is greater than 10gbit – use live migration with RDMA.

It does not matter if you are using 1gbit, 10gbit or 40gbit network connectivity – this guidance still holds.  It actually does not matter if you have RDMA support or not.  If you have over 10gbit network connectivity available for live migration – live migration over RDMA will get better performance thanks to SMB multichannel support.