Bug 484330

Summary:	ext3->ext4 migration doesn't enable extents
Product:	[Fedora] Fedora	Reporter:	Eric Sandeen <esandeen>
Component:	anaconda	Assignee:	Anaconda Maintenance Team <anaconda-maint-list>
Status:	CLOSED RAWHIDE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	low
Version:	rawhide	CC:	anaconda-maint-list, wwoods
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-02-20 19:03:17 UTC	Type:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	476774

Description Eric Sandeen 2009-02-06 05:12:08 UTC

Per my experience, and that during the Fedora ext4 test day (https://fedoraproject.org/wiki/QA/Test_Days/2009-02-05) doing an ext3->ext4 migration doesn't enable extents on the filesystem.

This would ideally be done pre-upgrade, if possible, so that the upgraded files (which should be most of them on the root) will be created in the extents format.

I'm not sure if this sort of "pre-upgrade-migration" fits well in the anaconda flow... but it's what we'd need to do for this sort of migration to be worthwhile.

Thanks,
-Eric

Comment 1 Will Woods 2009-02-19 16:53:29 UTC

Eric - what's required to enable extents? I assume it's a tune2fs call, as with the ext2->ext3 migration.

http://kernelnewbies.org/Ext4 suggests:
  tune2fs -O extents,uninit_bg,dir_index $DEV
  fsck -pf $DEV

Is that correct? Do we also want to enable the other listed features?

Comment 2 Eric Sandeen 2009-02-19 17:05:13 UTC

Yep, it's tune2fs, and the extent[s] option (either should work) is the critical one.

dir_index should already be enabled for any recent install.

uninit_bg may be helpful, depending on how full the filesystem is, but the subsequent fsck will take a while.  That one is a tossup I suppose, though you'll get better fsck times after that initial fsck.  I suppose we already run fsck from anaconda pre-resize(?) so there's precedent.

The key here, though, is that unlike the ext2->ext3 migration, this needs to be done before the packages are upgraded, not after, to get any benefit from the switch to extent format.

-Eric

Comment 3 Chris Lumens 2009-02-20 19:03:17 UTC

This should be fixed in the next build of anaconda.  Thanks for the info.