CPU for virtualization ?

drtech · July 30, 2018

I'm building out a new system for running around 5-6 VMs, but choosing a processor has been a tough decision for me

If I'm correct, hypervisors benefit from more cores than the actual clock speed per core, so by that, I should probably choose a Ryzen 2700 vs an Intel Core i7 8700, coupled with 32 gigs @ DDR4-2400.

However, while reading through forums, I came across some users having issues with Ryzen's AMD-V and IOMMU, it feels like I should stick to a lower thread count just cause of the extra reliability that Intel VT-x and VT-d offers ?

Have any of you folks tried running ESXi on Ryzen 2700 without facing any significant issues ?

Jon Jon · July 30, 2018

34 minutes ago, Ausaf Ahmad said:

I'm building out a new system for running around 5-6 VMs, but choosing a processor has been a tough decision for me

If I'm correct, hypervisors benefit from more cores than the actual clock speed per core, so by that, I should probably choose a Ryzen 2700 vs an Intel Core i7 8700, coupled with 32 gigs @ DDR4-2400.

However, while reading through forums, I came across some users having issues with Ryzen's AMD-V and IOMMU, it feels like I should stick to a lower thread count just cause of the extra reliability that Intel VT-x and VT-d offers ?

Have any of you folks tried running ESXi on Ryzen 2700 without facing any significant issues ?

I don't see an issue now that Ryzen has been around for a year and a half.

ESXi 6.5 had some pink screen of death issues with Ryzen a year ago that were ironed out.

Hyper-V should work without an issue.

At the end of the day, being someone that works with virtualization (among many other things at work), cores and memory allocation matter more than IPC.

What are you running for these 5-6 VMs? What's the overall purpose of this build?

To be honest, I would strongly consider Threadripper for the amount of VMs you want to run, as physical cores > logical cores if you are concerned with performance, especially since some applications are really only supported on physical cores when virtualized.

Ithanul · July 30, 2018

By the bit I have seen and read on using Ryzen and TR with ESXi, it pretty much boils down to the motherboard. Some work while others have crap IOMMU and controller issues when passthrough.

Probably the best thing is to ask this question on the actually VMWare forums for ESXi. But, even over there it seems documentation on using Ryzen is sparse.

DogKnight · July 31, 2018

I went down a similar path earlier this year.

Went to build a server for ESXI, and had a hard time deciding on hardware.

Eventually though I ended up using the new PC I built as a primary workstation and turned my old PC into the server. However this decision was only made after buying most of the parts.

The new build was with a 7820x. I wanted 8 cores but Ryzen just seemed not as reliable as Intel offerings. And by that I am referring to compatibility and support (not quality of the chip).

My old workstation that has become the ESXI server is using a 5820k. Both systems have 32gb of DDR4 RAM.

I have however installed ESXI on the new system within a VMWare Workstation which I can link up to my vCenter for extra resources if needed. Although with only a gigabit network, this is only ever a temporary measure.

Most of the storage resides on a Netgear ReadyNAS that is using bonded adapters.

Works well for a home lab. Keeping my eye out for a second hand 6900k at a reasonable price though to add a few more threads to my server. The biggest limitation I run into is RAM usage. Some of the VM's I run require 8-10gb of RAM and cannot be configured for less regardless of their workload. So it goes without saying that 32gb doesn't go too far. Waiting for DDR4 RAM prices to drop down a bit before purchasing some more.