For a research project we are trying to boot a very large amount of tiny, custom built VM's on KVM/ubuntu. The maximum VM-count achieved was 1000, but with substantial slowness, and eventually kernel failure, while the cpu/memory loads were nowhere near limits. Where is the likely bottleneck? Any solutions, workarounds, hacks or dirty tricks? A few more details here (tumbleweed question), and the possibility of an upvote: http://stackoverflow.com/questions/12243129/kvm-qemu-maximum-vm-count-limit Any tips would be much appreciated! Best regards, Alfred Bratterud Assistant Professor Dept. of Computer Science, Oslo and Akershus University College of Applied Sciences P: (+47) 2245 3263 M: (+47) 4102 0222