libvirt/tests/domainsnapshotxml2xmlout/noparent.xml

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<domainsnapshot>
<name>my snap name</name>
<description>!@#$%^</description>
snapshot: Don't expose testsuite-only state in snapshot XML None of the existing drivers actually use the 0-valued 'nostate' snapshot state; rather, it was a fluke of implementation. In fact, some drivers, like qemu, actively reject 'nostate' as invalid during a snapshot redefine. Normally, a driver computes the state post-parse from the current domain, and thus virDomainSnapshotGetXMLDesc() will never expose the state. However, since the testsuite lacks any associated domain to copy state from, and lacks post-parse processing that normal drivers have, the testsuite output had several spots with the state, coupled with a regex filter to ignore the oddity. It is better to follow the lead of other XML defaults, by not outputting anything during format if post-parse defaults have not been applied, and rejecting the default value during parsing. The testsuite needs a bit of an update, by adding another flag for when to simulate a post-parse action of setting a snapshot state, but none of the drivers are impacted other than rejecting XML that was previously already suspicious in nature. Similarly, don't expose creation time 0 (for now, only possible if a user redefined a snapshot to claim creation at the Epoch, but also happens once setting the creation time is deferred to a post-parse handler). This is also a step towards cleaning up snapshot_conf.c to separate its existing post-parse work (namely, setting the creationTime and default snapshot name) from the pure parsing work, so that we can get rid of the testsuite hack of regex filtering of the XML and instead have more accurate testing of our parser/formatter code. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Cole Robinson <crobinso@redhat.com>
2019-04-16 22:44:38 +00:00
<state>running</state>
<creationTime>1272917631</creationTime>
snapshot: new XML for external system checkpoint Each <domainsnapshot> can now contain an optional <memory> element that describes how the VM state was handled, similar to disk snapshots. The new element will always appear in output; for back-compat, an input that lacks the element will assume 'no' or 'internal' according to the domain state. Along with this change, it is now possible to pass <disks> in the XML for an offline snapshot; this also needs to be wired up in a future patch, to make it possible to choose internal vs. external on a per-disk basis for each disk in an offline domain. At that point, using the --disk-only flag for an offline domain will be able to work. For some examples below, remember that qemu supports the following snapshot actions: qemu-img: offline external and internal disk savevm: online internal VM and disk migrate: online external VM transaction: online external disk ===== <domainsnapshot> <memory snapshot='no'/> ... </domainsnapshot> implies that there is no VM state saved (mandatory for offline and disk-only snapshots, not possible otherwise); using qemu-img for offline domains and transaction for online. ===== <domainsnapshot> <memory snapshot='internal'/> ... </domainsnapshot> state is saved inside one of the disks (as in qemu's 'savevm' system checkpoint implementation). If needed in the future, we can also add an attribute pointing out _which_ disk saved the internal state; maybe disk='vda'. ===== <domainsnapshot> <memory snapshot='external' file='/path/to/state'/> ... </domainsnapshot> This is not wired up yet, but future patches will allow this to control a combination of 'virsh save /path/to/state' plus disk snapshots from the same point in time. ===== So for 1.0.1 (and later, as needed), I plan to implement this table of combinations, with '*' designating new code and '+' designating existing code reached through new combinations of xml and/or the existing DISK_ONLY flag: domain memory disk disk-only | result ----------------------------------------- offline omit omit any | memory=no disk=int, via qemu-img offline no omit any |+memory=no disk=int, via qemu-img offline omit/no no any | invalid combination (nothing to snapshot) offline omit/no int any |+memory=no disk=int, via qemu-img offline omit/no ext any |*memory=no disk=ext, via qemu-img offline int/ext any any | invalid combination (no memory to save) online omit omit off | memory=int disk=int, via savevm online omit omit on | memory=no disk=default, via transaction online omit no/ext off | unsupported for now online omit no on | invalid combination (nothing to snapshot) online omit ext on | memory=no disk=ext, via transaction online omit int off |+memory=int disk=int, via savevm online omit int on | unsupported for now online no omit any |+memory=no disk=default, via transaction online no no any | invalid combination (nothing to snapshot) online no int any | unsupported for now online no ext any |+memory=no disk=ext, via transaction online int/ext any on | invalid combination (disk-only vs. memory) online int omit off |+memory=int disk=int, via savevm online int no/ext off | unsupported for now online int int off |+memory=int disk=int, via savevm online ext omit off |*memory=ext disk=default, via migrate+trans online ext no off |+memory=ext disk=no, via migrate online ext int off | unsupported for now online ext ext off |*memory=ext disk=ext, via migrate+transaction * docs/schemas/domainsnapshot.rng (memory): New RNG element. * docs/formatsnapshot.html.in: Document it. * src/conf/snapshot_conf.h (virDomainSnapshotDef): New fields. * src/conf/domain_conf.c (virDomainSnapshotDefFree) (virDomainSnapshotDefParseString, virDomainSnapshotDefFormat): Manage new fields. * tests/domainsnapshotxml2xmltest.c: New test. * tests/domainsnapshotxml2xmlin/*.xml: Update existing tests. * tests/domainsnapshotxml2xmlout/*.xml: Likewise.
2012-10-23 15:12:23 +00:00
<memory snapshot='internal'/>
<domain>
<uuid>9d37b878-a7cc-9f9a-b78f-49b3abad25a8</uuid>
</domain>
</domainsnapshot>