Bug 1229843
| Summary: | sparseness is not preserved across online volume migration of a volume attached to an active VM | ||
|---|---|---|---|
| Product: | Red Hat OpenStack | Reporter: | Eoghan Glynn <eglynn> |
| Component: | openstack-nova | Assignee: | Kashyap Chamarthy <kchamart> |
| Status: | CLOSED WONTFIX | QA Contact: | OSP DFG:Compute <osp-dfg-compute> |
| Severity: | high | Docs Contact: | |
| Priority: | high | ||
| Version: | 15.0 (Stein) | CC: | asoni, byount, dasmith, dmaley, dsafford, eblake, eglynn, jraju, jwaterwo, kchamart, lyarwood, mbooth, sbauza, sgordon, spurrier, srevivo, vromanso |
| Target Milestone: | --- | Keywords: | Triaged, ZStream |
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Enhancement | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2019-10-15 09:17:58 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | 1232914, 1277471, 1297255, 1533975 | ||
| Bug Blocks: | |||
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Description
Eoghan Glynn
2015-06-09 18:48:47 UTC
Note bug #1219541 is tracking at least a very similar issue for libvirt and qemu. That bug is currently against the qemu component, though there is an upstream patch proposed against libvirt (though not yet merged): https://www.redhat.com/archives/libvir-list/2015-April/msg00130.html (In reply to Pádraig Brady from comment #3) > Note bug #1219541 is tracking at least a very similar issue for libvirt and > qemu. > > That bug is currently against the qemu component, though there is an > upstream patch proposed against libvirt (though not yet merged): > https://www.redhat.com/archives/libvir-list/2015-April/msg00130.html NB volume migration != guest migration. Volume migration is the code using the driveMirror libvirt API, but that quoted patch is for guest migration. Yes, this bug is purely for the online *volume* migration case. The guest stays put, but the volume needed to be moved between cinder backends in order to balance across multiple NetApps (in the customer usecase). live block volume migration has been disabled as of Kilo/RHOS 7 as per http://pad.lv/1398999 (and also in Juno if https://review.openstack.org/176768 is merged) Enablement will require: 1. Changes to qemu to detect zeros on NFS and propagate as holes (bug #1232914) 2. API changes to libvirt to make the operation safe (bug #1232919) 3. Nova changes to renable the feature and use the newer libvirt APIs (tracked in this bug) @pbrady, once again that (In reply to Pádraig Brady from comment #6) > live block volume migration has been disabled as of Kilo/RHOS 7 as per > http://pad.lv/1398999 > (and also in Juno if https://review.openstack.org/176768 is merged) These are again about *live migration* with block storage copy. ie the VM is relocated from one host to another host, and the storage is copied. This bug is about volume migration. The VM stays running on the current host, and the volume is swapped out from beneath it. Status update: Development is continuing in qemu, with another solution proposed, which is however a bit more invasive: http://lists.nongnu.org/archive/html/qemu-block/2015-06/msg00292.html http://git.qemu.org/?p=qemu.git;a=commitdiff;h=v2.3.0-1612-g0fc9f8e is scheduled to be backported next week to address this So this is still predicated on work in two lower layer components: (1) [libvirt] https://bugzilla.redhat.com/show_bug.cgi?id=1297255 — add possibility to sparsify image during block copy (2) [QEMU] https://bugzilla.redhat.com/show_bug.cgi?id=1533975 — detect-zeroes=unmap/on does not produce a sparse file on NFS v4.1 when attempting blockdev/drive-mirror I am closing this bug as it has not been addressed for a very long time. Please feel free to reopen if it is still relevant. |