Hi, KVM if used as it is will show very poor performance on CentOS5. To achieve better results you need to update kernel to at least 2.6.32 and compile newer versions of libvirt and qemu. On CentOS6 all is fine with KVM right out of the box. Never used XEN so cannot compare. Dmitry Cherkasov 2012/4/20 Rafał Radecki <radecki.rafal at gmail.com>: > Hi all. > > I am currently building a small test cloud based on Eucalyptus 2.0.3 and > CentOS 5.8 x64. I have a choice which hypervisor to use: KVM or XEN. > KVM is the default in CentOS 6 but I have read also many good things (for > example PV guest machines, isolation between Dom0 and DomU) about XEN. > > Key factors from my opint of view are: > - stability (which one runs more smoothly on CentOS?) > - performance (XEN PV/HVM(with or without pv drivers) vs KVM HVM(with or > without pv drivers)) > - security > > Could you share your experience in these areas? > > Best regards, > Rafal Radecki. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos