Virtual machines, what CPU is best?

R3X

R3X

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Hi bit new to running virtual machines was planning on using Virtualbox but am trying to find out which cpu is best. I would like to run perhaps 1-2 virtual machines perhaps ubuntu and more will have 16gig ram also.

Googled and read quite a few were suggesting AMDs 8350 8 core cpus would be better then intels quad offerings?

But then I still play some games so was perhaps considering 4770/4790k, I do not know if intels HT technology helps though and also intels 5820K coming next month with a 6 core cpu perhaps this is a better option to wait for since its 6 real cores and intel based?

Any suggestions would be appeciated thanks
 
Ram is farm more important than cpu power for virtualisation.

I quite easily ran 4 vm's. 3 debian 1 server 2008 r2 on a Sempron x2 190 2.7ghz dual core with perfectly adequate performance
 
I'm happily running a host and vm with a further 3 vm shared on my 3820. Very little if any bog down. 3930 would be ideal in my opinion if you need to run more or more complex than coding/compiling/emulator activities.
 
I think for now just even 1 or 2 vms nothing too heavy or serious, I find it interesting the replies above since an 3820 4 core intel chip did fine with 3 vms and froze mentioned ram was more important while running 4 vms with a dual core 2.7ghz amd budget cpu.

Perhaps I think with a 4770k/4970 with 16gig it would be more then ample and waiting on a 6 core intel cpu could be overkill.

Any more ideas are welcome if not interesting !
 
I guess it does make sense that I say my 4 VMs were osx variants. Which would probably require more horsepower than a Debian system(I think).

Ram is definitely a bottleneck I originally had 8gb of ram and it was ok but bogged down quickly. 16gb and I notice very little bog down however I am looking at jumping to a 32gb or 64gb soon.

I am somewhat a novice with vm but to my limited knowledge/experience ram and ssd are the things that will make the most of your system a cpu bottleneck with only come into play when you're running more than a vm per cpu thread.

For example I can happily run 12 vm at the same time with light loads on my cpu (70% utilised) but my 16gb ram and SSDs are at 95% utilisation. (However this could be down to my limited knowledge on setting them up efficiently).
 
OS x would be a lot heavier than my vm's.

For reference they we're all Debian 7 x64 with no gui so command line only server the following purposes
VM 1 - zfs file server, mysql db for xbmc, deluge, Sickbeard, couchpotato
VM2 - Virtualmin server proving apache, mysql, mail and dns
vm3 - general test box box before.
vm4 - server 2008 r2, domain controller and Windows update server.

Again SSD will also play a big part, I ran that lot off a single 5400rpm laptop drive and disk io was the only cause of any slow down
 
Some CPUs have hardware functions relevant for virtual machines but whether you would be using a setup that actually makes use of that or not is another matter and a longer topic of its own possibly i.e. the IvyBridge-E CPUs like the 4820K supports VT-d (direct IO) functionality as well as extra VT-x features that aren't supported on the Haswells like the 4770K.

The extra cores and HT units of the 3930K or similar could be useful for extensive VM use even if you don't make use of the extra VT- features.
 
Some CPUs have hardware functions relevant for virtual machines but whether you would be using a setup that actually makes use of that or not is another matter and a longer topic of its own possibly i.e. the IvyBridge-E CPUs like the 4820K supports VT-d (direct IO) functionality as well as extra VT-x features that aren't supported on the Haswells like the 4770K.

The extra cores and HT units of the 3930K or similar could be useful for extensive VM use even if you don't make use of the extra VT- features.

This is a very good point. If you want to do anything fancy like pass through a graphics card, or a HDD controller card or something from the physical hardware to one of the VMs then you will need to have the relevant extensions on the CPU. Modern Xeon chips starting from the E3-1220 should have everything you need.
 
Wouldn't a Xeon chip be a bit overkill for what the op is describing?

I always thought Xeon were aimed at 24/7 stable greater than 50% loads for servers or high end workstations for multi-cpu ability/pure grunt.

Apologies if I'm wrong I just didn't think they were worth the extra for your average home user.
 
This is a very good point. If you want to do anything fancy like pass through a graphics card, or a HDD controller card or something from the physical hardware to one of the VMs then you will need to have the relevant extensions on the CPU. Modern Xeon chips starting from the E3-1220 should have everything you need.

Anything from i5 up supports vt-d as long as it's not a K series cpu.

It's a little more complicated with AMD as every cpu from am3 and up support its but it's difficult and not very well documented on motherboards that have the required IOMMU support. The Asrock 970 extreme 3/4 are mentioned as being supported and I am using hardware pass thru with ESXI with the Asrock 970 pro3
 
Ram is farm more important than cpu power for virtualisation.

I quite easily ran 4 vm's. 3 debian 1 server 2008 r2 on a Sempron x2 190 2.7ghz dual core with perfectly adequate performance

Have to disagree!!

Some CPUs have hardware functions relevant for virtual machines but whether you would be using a setup that actually makes use of that or not is another matter and a longer topic of its own possibly i.e. the IvyBridge-E CPUs like the 4820K supports VT-d (direct IO) functionality as well as extra VT-x features that aren't supported on the Haswells like the 4770K.

The extra cores and HT units of the 3930K or similar could be useful for extensive VM use even if you don't make use of the extra VT- features.

There are some intel chips, like the 'K' models which do not support and to confuse this more, I know some of the new Devils Canyon CPUs do, but you need to make sure you buy the right one.

Get a 2nd hand i7 3820 and you're all set.
 
Wouldn't a Xeon chip be a bit overkill for what the op is describing?

I always thought Xeon were aimed at 24/7 stable greater than 50% loads for servers or high end workstations for multi-cpu ability/pure grunt.

Apologies if I'm wrong I just didn't think they were worth the extra for your average home user.

Your not wrong but often/sometimes Xeons can be picked up cheap and otherwise identical to the equivalent desktop CPU when enterprise use starts to move onto a newer version of the CPU (sometimes can be issues getting them recognised by desktop boards though).
 
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Wouldn't a Xeon chip be a bit overkill for what the op is describing?

I always thought Xeon were aimed at 24/7 stable greater than 50% loads for servers or high end workstations for multi-cpu ability/pure grunt.

Apologies if I'm wrong I just didn't think they were worth the extra for your average home user.

Well the E3-1220 is only about £150, so it's cheaper than the i7 chip that some people have suggested. The E3 series is oriented more at workstations than servers.

It depends what the OP is planning to do with the VMs - if it's just basic stuff like running Linux to do some training or host a web server or something then desktop class CPUs will be fine. Complicated stuff involving hardware pass-through will need some more thought.
 
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Not sure about hardware pass thru capabilities it was more to set up vms to try xmbc, or run ubuntu as a download/movie + media machine.

Would also like to try and dabble and learn other linux distros and dedicate them to specifics ie have one dedicated for movie playback and perhaps xpenology/nzb box.

I have run 1080p movie trailers via a VM ubuntu setup and it looked excellent as good as on the original pc, but this was on an Core i5 2400 with a 1gig GPU card.
 
makes the 4970k my main choice really if it supports those vm features I was thinking why would intels latest and top chip not sport the latest features.

thanks for all the input guys
 
4970k would be a lot cheaper to run as well :)

Pretty sure its faster than my 3820 in every aspect as well so well worth it.

Although my 3820 is mine so that makes it equivalent to a cray machine :D


Edit: although double check the mobo you get. I have a friend who's cpu was capable of vtx but for some unknown reason the mobo wouldn't allow him to turn it on.
 
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