Proxmox Templates 32.bit

[Chris Rivera]

I've read enough posts that let me know proxmox development team does not like 64 bit images...

i understand they use more resources but have the benefit or faster processing for specific uses.

Is it possible for your kernel to have PAE so that we can use more thant 3.1gb ram on 32 bit vms?


This i believe would provide the best of both worlds.... we can use 64 bit if required.... or we can use 32bit image with more than 3 gb of ram.

 

[mir]

AFAIK resent kernels from all distributions will use 686-pae or 586-pae kernels by default

 

[Chris Rivera]

sorry but this was over my head. could you explain that.

thanks mir

 

[mir]

If you create a 32 bit kvm and install any distribution it will most likely automatically install a 32 bit kernel with pae extension.

 

[Chris Rivera]

Understood. Sorry i was not clear.

I was talking about the Main kernel for linux for use with openvz.

 

[mo_]

its actually the other way round tho, 64bit containers are really the only containers you should install - ever. theres absolutely no point in using 32bit still, linux guys are just somewhat conservative when it comes to removing legacy tech. thats the reason why the linux kernel still has ISA support in it and openvz still offers 32bit templates in addition to the real 64bit templates.

 

[mir]

The main kernel in Proxmox is 64 bits so the kernel in openvz will therefore also be 64 bits. The templates named 386 indicating 32 bit means that userland is running 32 bit and this is the problem in relation to memory available for an application. A 32 bit application cannot consume more than 2 GB of memory even if the amount of memory is more than 2 GB but if none of your application will ever need more than 2 GB of memory then this barrier will not be a problem.

 

[Chris Rivera]

I will agree to disagree.

32bit images should be default when 64bit and 3.1gb+ ram is not required.
64bit images should be used when 64bit is required.

As a provider of VPS hosting you need to be able to fit as many machines as you can on a node which is the reason why Dietmar explains 32bit are the proxmox default templates. 32bit images use less resources which is better in the end for a provider.

64bit images while available ( from openvz ) are not available from the proxmox default repository unless you are using the appliances. 64bit unless required, from a host perspective, is not the best way to go which is the reason why i present such a question.

If a client does not need 64bit and could use 32bit, this would be preferred but if the client needs more than 4gb ram they can only access that by having a 64bit image or unless the kernel was PAE... 32bit systems with PAE kernel are able to access more ram.

Proxmox is a 64bit kernel, but when a 32bit image is spawned cannot access more that 3.1 - 4 gb ram. But if the 64bit kernel has PAE loaded into it, we can essentially spawn 32bit images that can support more than 3.1 - 4gb ram.


I know its kind of weird to be asking for PAE to be loaded in a 64bit kernel, but from openvz perspective this makes perfect sense.

 

[mo_]

a commercial(!) hosting environment is, at least to my understanding, not the primary intended usage of proxmox. while it may be usable for that, I feel like it would be wrong to implement changes towards something thats not the project's primary goal, especially since its a legacy technology (lets not forget that).

also the only reason 64bit containers use more resources is because a 64bit linux also needs to keep 32bit binaries around to support this legacy architecture. if it didnt need to keep those, it would have roughly the same storage footprint.

Lastly, I would disagree that you need to fit as many VEs on a server as possible. What you need is to supply good performance, which you cant get from oversaturating your boxes.

PS: proxmox does offer 64bit containers from its "default repository" which is essentially this directory: http://download.proxmox.com/appliances/system/

 

[JimBeam]

Storage is not only resource involved. IIRC 64 bit programs take up more memory because they use 64 bit registers instead of 32 bit ones for their variables.

And as for "fit as many VEs on a server as possible.": depends on what you mean by possible. I'm sure Chris meant "possible in the sense that the performance meets requirements" but didn't feel the need to spell it out

 

[Chris Rivera]

a commercial(!) hosting environment is, at least to my understanding, not the primary intended usage of proxmox.

Whether we use it as a public cloud or private cloud that's not the point. It works for both and i can tell you for the most part its works perfectly well in both environments. ( as long as you don't oversubscribe it too much ) Obviously the preferred setup would be a private cloud, but unless you need a private cloud public environment VPS is all good. If you need a non oversubscribed VPS you should invest in your own private cloud and shouldnt be shopping for a public cloud vps.

Proxmox is a WORKING virtual environment period. It provides a stable KVM ( windows / linux ) OpenVZ ( linux ) environment which is all a VPS customer needs.


Also I did mention in my post that 64bit appliances are available, just not operating systems.

64bit images while available ( from openvz ) are not available from the proxmox default repository unless you are using the appliances.

Storage is not only resource involved. IIRC 64 bit programs take up more memory because they use 64 bit registers instead of 32 bit ones for their variables.

Certain applications will use more resources because of the 64bit architecture. MySQL i believe is another one. That's normal because of the speed and extra capabilities that a 64bit system can utilize such as more ram.


Now going back to my original question... Could a 64bit Proxmox Kernel Include PAE so that the default 32bit operating systems can get access to more ram? If so this would be the best of both worlds

Applications with no use for 64bit architechture which only need extra ram available could definitely benefit by using a 32bit images with PAE loaded to access 5-6gb of ram... Less resources used for the environment and more ram available for use by the application.