Bug 1913389

Summary:	[CBT] [RFE] Provide VDSM with more information on scratch disks
Product:	[oVirt] ovirt-engine	Reporter:	Nir Soffer <nsoffer>
Component:	Backup-Restore.VMs	Assignee:	Pavel Bar <pbar>
Status:	CLOSED CURRENTRELEASE	QA Contact:	sshmulev
Severity:	high	Docs Contact:	bugs <bugs>
Priority:	high
Version:	future	CC:	aefrat, ahadas, bugs, bzlotnik, eshames
Target Milestone:	ovirt-4.5.0	Keywords:	CodeChange, FutureFeature, ZStream
Target Release:	4.5.0	Flags:	pm-rhel: ovirt-4.5? pm-rhel: planning_ack? pm-rhel: devel_ack+ pm-rhel: testing_ack?
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	vdsm-4.50.0.10 ovirt-engine-4.5.0	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-03-16 13:03:54 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	Storage	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1913387, 2021545
Bug Blocks:

Description Nir Soffer 2021-01-06 16:04:07 UTC

Description of problem:

Currently engine need to create scratch disk using the actual size of backup
disk. When the backup disk is using raw format, this needs very large scratch
disk that that in most case will not be used. Since we don't know how much 
data the guest will write to the disk during the backup, we cannot create a
smaller scratch disk.

When working with host supporting scratch disk block threshold monitoring,
create scratch disk on block storage with small initial size. Vdsm will
monitor the scratch disk block threshold and extend it as needed.

Monitoring scratch disk block threshold will be available in RHEL 8.4, see
bug 1913315. Vdsm may be able to monitor and extend scratch disks in 
ovirt 4.4.6 or 4.4.7.

Comment 2 Sandro Bonazzola 2022-04-20 06:32:24 UTC

This bugzilla is included in oVirt 4.5.0 release, published on April 20th 2022.

Since the problem described in this bug report should be resolved in oVirt 4.5.0 release, it has been closed with a resolution of CURRENT RELEASE.

If the solution does not work for you, please open a new bug report.