Bug 814833

Summary:	dm-thin: handle running out of data or metadata space cleanly
Product:	Red Hat Enterprise Linux 6	Reporter:	Alasdair Kergon <agk>
Component:	kernel	Assignee:	Joe Thornber <thornber>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Cluster QE <mspqa-list>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	6.4	CC:	agk, dwysocha, heinzm, jbrassow, msnitzer, prajnoha, prockai, thornber, zkabelac
Target Milestone:	rc	Keywords:	FutureFeature
Target Release:	---
Hardware:	Unspecified
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-11-21 18:36:27 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:	814826
Bug Blocks:

Description Alasdair Kergon 2012-04-20 19:23:02 UTC

If a thin pool runs out of space (for data or metadata) either

a) gracefully make the device read-only

or

b) queue further write I/O until more space is supplied to the device

according to a configuration option.  (Similar to mpath's queue_if_no_path.)

Comment 1 RHEL Program Management 2012-07-10 08:25:26 UTC

This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.

Comment 2 RHEL Program Management 2012-07-10 23:36:45 UTC

This request was erroneously removed from consideration in Red Hat Enterprise Linux 6.4, which is currently under development.  This request will be evaluated for inclusion in Red Hat Enterprise Linux 6.4.

Comment 3 Mike Snitzer 2012-11-21 18:36:27 UTC

If data fills then the low water mark will have been triggered and the associated thin device will queue IO waiting for userspace to add more space to the pool.

If metadata fills the thin pool should switch to read-only mode.