If I understood you right, your approach is a suspend VM via ACPI mechanism, then dump core, then restore it - this should be longer than simple coredump due timings for guest OS to sleep/resume, which seems unnecessary. Copy-on-write mechanism should reduce downtime to very acceptable values but unfortunately I do not heard of such mechanism except academic projects. On Sat, May 18, 2013 at 5:48 PM, Dzianis Kahanovich <mahatma@xxxxxxxxxxxxxx> wrote: > IMHO interaction QEMU & kernel's FREEZER (part of hibernation & cgroups) can > solve many of problems. It can be done via QEMU host-2-guest sockets and scripts > or embedded into virtual hardware (simulate real "suspend" behavior). > > Andrey Korolyov пишет: >> Hello, >> >> I`ve thought of the same mechanism a lot ago. After couple of tests I >> have concluded that coredump should be done not to Ceph directly, but >> to the tmpfs catalog to decrease VM` idle timeout(explicitly for QEMU, >> if other hypervisor able to work with Ceph backend and has COW-like >> memory snapshotting mechanism, time of the 'flush' of the coredump >> does not matter). Anyway, with QEMU relatively simple shell script >> should do the thing. >> >> On Sat, May 18, 2013 at 4:51 PM, Jens Kristian Søgaard >> <jens@xxxxxxxxxxxxxxxxxxxx> wrote: >>> Hi guys, >>> >>> I was wondering if anyone has done some work on saving qemu VM state (RAM, >>> registers, etc.) on Ceph itself? >>> >>> The purpose for me would be to enable easy backups of non-cooperating VMs - >>> i.e. without the need to quiesce file systems, databases, etc. >>> >>> I'm thinking an automated process which pauses the VM, flushes the Ceph >>> writeback cache (if any), snapshots the rbd image and saves the VM state on >>> Ceph as well. I imagine this should only take a very short amount of time, >>> and then the VM can be unpaused and continue with minimal interruption. >>> >>> The new Ceph export command could then be used to store that backup on a >>> secondary Ceph cluster or on simple storage. >>> >>> -- >>> Jens Kristian Søgaard, Mermaid Consulting ApS, >>> jens@xxxxxxxxxxxxxxxxxxxx, >>> http://www.mermaidconsulting.com/ >>> _______________________________________________ >>> ceph-users mailing list >>> ceph-users@xxxxxxxxxxxxxx >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> >> > > > -- > WBR, Dzianis Kahanovich AKA Denis Kaganovich, http://mahatma.bspu.unibel.by/ > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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