SSD for Host PVE OS will help in VMs performance?

[FcbInfo]

Hi there.

It's only to confirm, but I believe will get no differences on VMs if you install the Proxmox in a separated SSD or in the same HDD of that you will host RAW files.

The Proxmox host OS consume some IOPs to run VMs? (I believe not).

Is there some differences if you use OpenVZ or KVM?
I always use KVM and had no experience with OpenVZ, but I will start to use in some days.

Thanks for help and sorry for the bad English!

 

[thheo]

It should not make any difference except for the moment you start using the swap of the host..

 

[FcbInfo]

Hm... OpenVZ can use Swap of the Host?

KVM don't use it for sure. Swap is inside the RAW file!

Thanks for help!

 

[udo]

It should not make any difference except for the moment you start using the swap of the host..

Hi,
if the host start to use swap you will allways have an big performance-problem...

 

[thheo]

Of course, but it will make a difference if the swap is on ssd You should have enough RAM not to ever swap..

 

[FcbInfo]

I never use OpenVZ but in the times that I have used OpenVZ for test, (on my old SolusVM control panel), that have a field to config swap size.
This swap of the openvz vms, use swap of the host or that use in the same disk of openvz vm is installed?

 

[mir]

It should not make any difference except for the moment you start using the swap of the host..

This is not true. When doing backup, migration, upload images, moving disks etc. disk access is required by proxmox and if disk is shared with VMs, and especially the VMs operating on, you will only have approximately half the IOPS since VM and proxmox operates on the same disks. On the other hand if VMs are stored on shared storage then this is eliminated. So if your are hosting VMs locally you should separate root and /var/lib/vz on different disks. Using a hardware raid controller will of course positive narrow the gap between using the same disk/array and separating them.

 

[thheo]

The way I read it, it's not what he asked..
However what you mentioned above, would be a better practice ofc.

 

[FcbInfo]

I believe it's better to get an SSD for the host OS. Only more $15 / month.

The doubt now is only on the OpenVZ Swap.

I'm reading this now, maybe will solve my doubt: http://www.jamescoyle.net/how-to/622-proxmox-openvz-swap-and-performance