Yep the module is loaded. VT is enabled in the bios as well.

Odd, I'm installing CentOS now as another test and it actually seems to be going pretty quick. The only thing I can think that I did different is I premade the disk using dd and I'm doing it from home instead of the office through the VPN. (just the X session to the server). Could the X session's location somehow affect how fast it's actually running? I can't see why, since it's just a display protocol, if the screen can't draw fast enough that should not actually stop the process itself.

I will do windows 7 again using the same method and see how it goes.

Edit: Spoke too soon, the entire VM just locked right up while I make the disk for the next VM. I could understand it getting a bit slower, but completely locking up? The mouse movement restored as soon as the disk was done creating but it's still stuck at installing the same package. This sounds like disk IO but I know it's not, I've had as much as 7 Vbox VMs (2 game servers + mysql backend) running off my core2quad machine on this same storage system, and it would take whatever I throw at it.

Could you just indulge me, and use virtio for disk and network?
It's not going to take much of your time.

Just because your back-end has no I/O issues it doesn't mean your front-end lacks them as well.

What do I have to do to use that? I keep reading about it but nothing shows how to actually do it. They sometimes talk about xml files, but they don't see WHERE those xml files are.

Actually I think I just found it if I go in details, IDE disk 1 then under performance, but the VM is already created. When you create a VM it never prompts for any of that, it just wants to start installing right away and you don't have a chance to go look at the rest of the settings.

Though I'm starting to think I might just say screw it and go ESXi. Another issue I noticed is everything seems to require the guest to be shut down, including changing CD!!! Totally unacceptable. I was really hoping to use open source though but it seems this is clearly not geared towards production and high availability. Lot of the tutorials I keep reading also require to restart the host networking service to make changes! That is about the most risky thing you can do on a remote machine. Unless there's something I can do so it does not require to be restarted for everything? Any setting I change says it will only take affect when the guest is shut down.

Ok so I just shut down that guest and started to reinstall windows but now it wont detect the drive. I'm guessing I have to load some kind of driver. I googled for virtio driver and found an ISO. But when I change the CD the change only takes affect on guest shut down? So how do I do this? Though all this deal of having to shut down to make trivial changes is probably enough to make me give up unless there's a way around this.

Edit: Ok so I ended up just adding two cdrom drives so I can have two CDs in at once.

It's installing now, Expanding Windows Files is already at 3%, usually it would sit at 0 for a good half hour or more. So maybe this is actually the issue.

Though if I really do have to shut down the guest for every trivial change such as adding a CD, I might reconsider using this solution. Unless there's a way around this limitation that's not too extreme. Seems a lot of sacrifices have to be made with open source sometimes.

Well that's not a good sign, it's stuck at "Windows is starting services" for like 10 minutes now.

Though I'm also installing Debian and that one seems to be going smooth. Could it just be that windows is unstable under KVM? I don't really plan to have that many windows VMs, but it would be good if it actually did work.

edit: 3:30pm: So it's done installing now (had to force reboot it when it got stuck). I guess it's a bit faster than before. Took about an hour instead of 3.

Allocated one what? One thread of a hyperthreaded core? if so that is why it is slow. To be done right you have allocate the entire core (not necessarily easy unless you disable hyperthreading).

Whaaa? Never had to do that with any other hypervisor. I've always just assinged 1/8 cores (4 core but shows up as 8 due to ht). DISABLE hyperthreading?! Is KVM really this primitive? I guess I will have to go to vmware. That or virtualbox, but virtualbox is kinda a pain to manage as you need the VM windows up all the time, so you have to run a GUI on the server and VNC in.

1 core is still 3.5Ghz, there is zero reason why basic things like installing windows should be this slow.

Though, virtio makes it half decently acceptable. I need to do more performance testing, but if there is any way things like changing CDs can be done without a VM reboot I may be able to stay with kvm.

Yeah this is just way too flaky. Debian stuck at a gray screen for no reason now. Going to have to look at another solution. VMware will be a pain since they don't have a Linux client, so I'm really at a loss. VirtualBox so far is the only Linux VM program that works properly, it's just that it's really dirty to manage.

When you have hyperthreading you don't get a full core. You get maybe 1.5. The ".5" is available for hyperthreading. If your system is relatively busy, that means that the "core" being used for your VM is less than half a core - and thus very very slow. It has been a while, but I think VMware allocates two threads (an entire core) when you assign it a core. This makes it run much faster.

Can I just assign 2 cores and it will automaticaly use one real core? I suppose I could assign all 8, but then if I have a VM where the software inside is acting up it could take out all other VMs as it will just hog the cpu.

Though now I'd say my biggest issue is the fact that I can't do basic tasks such as change the cd or network bridge without powering off the VM. Is this really how it is? Or is there a way around that?

It also seems very flaky in the video display department, lot of GUIs act all screwy, but I rarely use GUIs in actual production VMs so I guess it's not that huge of an issue.

I really want to use KVM as it's open source and all the other solutions I tried like xen and proxmox are meh, but I'm just finding it has lot of little issues like this. I hope I can get it sorted out.

Most modern software and OS's handle HT well. I tend to keep it enabled.


Assign all the cores you have to all vm's. The system will level out load on it's own. You limit cores based on other factors.

To test, you can disable HT if you want for a test.

Run all the cores you have for a test. (seems I wrote that already)

Ok I will try all cores, I just never did it that way before and when I did, I ran into issues, but maybe it was that particular implimentation that did not like that. I'll try it and see how it goes.

Anyone know if there's any way to hot plug stuff though? If I really have to shut down a VM just to change the cd or network interface, I will have to call it quits because that's just not acceptable for my environment. I also need the ability to "unplug" the network cable. Sometimes I have various test stuff going on where I need to do that. When I make any changes, even very basic, it tells me it will only take affect when the guest shuts down.

Ok so allocating all cores definitly seems to help, so does using virtio. At least for Windows 7 and Debian, those are the two main OSes I've been testing (wanted to stick to the same ones so I can better gauge the install time and so on)

Now if I can somehow find an easy way to hot plug stuff and figure out the vlan bridging so I don't have to restart networking or even reboot after a change, this solution may actually be viable for my needs.

Everything I've read suggests that if you don't have hardware virtualization enabled in the BIOS, the vmx module wont load.
KVM reference