On 18.08.2012 04:08, Eric Blake wrote:
I've determined that it is possible to mix migration to file with disk snapshots on existing qemu 1.1 in such a way to take a live system checkpoint snapshot of a system without the downtime of either 'virsh snapshot-create' or 'virsh save'; without the loss in disk state of 'virsh save'; and without the fsck penalties of 'virsh snapshot-create --disk-only'; basically by combining the best of those three approaches.
I'm also quite tired of 'virsh snapshot-create --disk-only' failing for an offline domain, and have upcoming patches to drive qemu-img to do that for an offline image.
Unfortunately, qemu 1.2 missed out on adding the 'drive-mirror' or 'block-commit' commands, so I still can't do quite everything I want with snapshots (in particular, I can't preserve the original filename; although you can do a snapshot/blockpull/snapshot to get back to the original filename with twice the work). But I think this series still leaves room for future enhancements as future qemu provides the means.
Although I'm still in the middle of polishing the src/qemu patches, I'd at least like to post this series of prep-work to document how I plan to expose it all, and to make sure my design decisions are on track. The first three can be applied now, the fourth should probably not be applied until I actually have later patches using the new XML, hopefully still in time for 0.10.0.
Eric Blake (4): snapshot: make virDomainSnapshotObjList opaque snapshot: split snapshot conf code into own file snapshot: rename an enum snapshot: new XML for external system checkpoint
docs/formatsnapshot.html.in | 11 + docs/schemas/domainsnapshot.rng | 23 + po/POTFILES.in | 1 + src/Makefile.am | 3 +- src/conf/domain_conf.c | 933 +----------------- src/conf/domain_conf.h | 143 +-- src/conf/snapshot_conf.c | 1021 ++++++++++++++++++++ src/conf/snapshot_conf.h | 160 +++ src/esx/esx_driver.c | 1 + src/libvirt_private.syms | 5 +- src/qemu/qemu_command.c | 1 + src/qemu/qemu_domain.c | 7 +- src/qemu/qemu_domain.h | 3 +- src/qemu/qemu_driver.c | 69 +- src/qemu/qemu_migration.c | 2 +- src/vbox/vbox_tmpl.c | 1 + tests/domainsnapshotxml2xmlin/external_vm.xml | 10 + tests/domainsnapshotxml2xmlin/noparent.xml | 9 + tests/domainsnapshotxml2xmlout/all_parameters.xml | 1 + tests/domainsnapshotxml2xmlout/disk_snapshot.xml | 1 + tests/domainsnapshotxml2xmlout/external_vm.xml | 43 + tests/domainsnapshotxml2xmlout/full_domain.xml | 1 + tests/domainsnapshotxml2xmlout/metadata.xml | 1 + tests/domainsnapshotxml2xmlout/noparent.xml | 1 + .../noparent_nodescription.xml | 1 + .../noparent_nodescription_noactive.xml | 1 + tests/domainsnapshotxml2xmltest.c | 1 + 27 files changed, 1365 insertions(+), 1089 deletions(-) create mode 100644 src/conf/snapshot_conf.c create mode 100644 src/conf/snapshot_conf.h create mode 100644 tests/domainsnapshotxml2xmlin/external_vm.xml create mode 100644 tests/domainsnapshotxml2xmlin/noparent.xml create mode 100644 tests/domainsnapshotxml2xmlout/external_vm.xml
Eric, I could apply the first patch (however using 3-way merge) but cannot the second. Can you please (rebase? and) resend? Or is this intended to be applied on the top of another patchset: Applying: snapshot: split snapshot conf code into own file fatal: sha1 information is lacking or useless (src/conf/domain_conf.c). Repository lacks necessary blobs to fall back on 3-way merge. Cannot fall back to three-way merge. Patch failed at 0001 snapshot: split snapshot conf code into own file When you have resolved this problem run "git am --resolved". If you would prefer to skip this patch, instead run "git am --skip". To restore the original branch and stop patching run "git am --abort". Michal