I just wanted to point out that we've this patch in Debian since ages, and it's been included in upstream for a long time too. Added a debbug reference for this as well.
** Bug watch added: Debian Bug tracker #597517 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=597517 ** Also affects: qemu-kvm (Debian) via http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=597517 Importance: Unknown Status: Unknown -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/524447 Title: virsh save is very slow Status in libvirt virtualization API: Unknown Status in QEMU: Fix Released Status in “libvirt” package in Ubuntu: Invalid Status in “qemu-kvm” package in Ubuntu: Fix Released Status in “libvirt” source package in Lucid: Won't Fix Status in “qemu-kvm” source package in Lucid: Won't Fix Status in “libvirt” source package in Maverick: Won't Fix Status in “qemu-kvm” source package in Maverick: Won't Fix Status in “qemu-kvm” package in Debian: Unknown Bug description: ================================== SRU Justification: 1. impact: 'qemu save' is slow 2. how addressed: a patch upstream fixes the case when a file does not announce when it is ready. 3. patch: see the patch in linked bzr trees 4. TEST CASE: see comment #4 for a specific recipe 5. regression potential: this patch only touches the vm save path. ================================== As reported here: http://www.redhat.com/archives/libvir- list/2009-December/msg00203.html "virsh save" is very slow - it writes the image at around 1MB/sec on my test system. (I think I saw a bug report for this issue on Fedora's bugzilla, but I can't find it now...) Confirmed under Karmic. To manage notifications about this bug go to: https://bugs.launchpad.net/libvirt/+bug/524447/+subscriptions