Change in vdsm[master]: image: avoid prezeroing optimization in some cases

danken at redhat.com danken at redhat.com
Thu Oct 18 13:25:32 UTC 2012


Dan Kenigsberg has submitted this change and it was merged.

Change subject: image: avoid prezeroing optimization in some cases
......................................................................


image: avoid prezeroing optimization in some cases

The prezeroing optimization should be used only when it is actually
stricly required. Using such optimization with COW is dangerous since
the qcow2 header would contain the temporary volume size (10Mb).

Until now this wasn't a problem because the content of the volume
(qcow2 header included) would have been replaced by the original
content (during a copy), with the introduction of live storage
migration this might become a problem because the leaf is actually
used for mirroing.

Change-Id: I9b8f348af355b0f17ab66dd9d5ef57c905051c17
Signed-off-by: Federico Simoncelli <fsimonce at redhat.com>
---
M vdsm/storage/image.py
1 file changed, 30 insertions(+), 11 deletions(-)

Approvals:
  Ayal Baron: Looks good to me, approved
  Federico Simoncelli: Verified
  Allon Mureinik: Looks good to me, but someone else must approve
  Dan Kenigsberg: 
  Igor Lvovsky: Looks good to me, but someone else must approve


--
To view, visit http://gerrit.ovirt.org/7935
To unsubscribe, visit http://gerrit.ovirt.org/settings

Gerrit-MessageType: merged
Gerrit-Change-Id: I9b8f348af355b0f17ab66dd9d5ef57c905051c17
Gerrit-PatchSet: 6
Gerrit-Project: vdsm
Gerrit-Branch: master
Gerrit-Owner: Federico Simoncelli <fsimonce at redhat.com>
Gerrit-Reviewer: Allon Mureinik <amureini at redhat.com>
Gerrit-Reviewer: Ayal Baron <abaron at redhat.com>
Gerrit-Reviewer: Dan Kenigsberg <danken at redhat.com>
Gerrit-Reviewer: Eduardo <ewarszaw at redhat.com>
Gerrit-Reviewer: Federico Simoncelli <fsimonce at redhat.com>
Gerrit-Reviewer: Igor Lvovsky <ilvovsky at redhat.com>
Gerrit-Reviewer: Saggi Mizrahi <smizrahi at redhat.com>
Gerrit-Reviewer: Shu Ming <shuming at linux.vnet.ibm.com>
Gerrit-Reviewer: Vered Volansky <vvolansk at redhat.com>


More information about the vdsm-patches mailing list