= Proposed Self Contained Change: LVM Cache Logical Volumes =
https://fedoraproject.org/wiki/Changes/Cache_Logical_Volumes
Change owner(s): Alasdair G. Kergon <agk(a)redhat.com>, David Cantrell
<dcantrel(a)redhat.com>, Dave Lehman <dlehman(a)fedoraproject.org>
LVM can now use fast block devices (e.g. SSDs and PCIe Flash) to improve the
performance of larger but slower block devices. These hierarchical or layered
logical volumes are called Cache Logical Volumes in LVM.
== Detailed Description ==
LVM is now capable of using fast block devices (e.g. SSDs) as write-back or
write-though caches for larger slower block devices. Users can create cache
logical volumes to improve the performance of their existing logical volumes
or create new cache logical volumes composed of a small and fast device
coupled with a large and slow device. These cache logical volumes can be used
with most LVM segment types, including RAID 1/4/5/6/10, linear, stripe and
thin pools.
== Scope ==
* Proposal owners:
The LVM team must deliver the lvm2 package implementing cache LV (already
included in release 2.02.106)
* Other developers: N/A (not a System Wide Change)
The Anaconda team must develop a UI for configuring cache LVs during
installation. If Anaconda support is not provided, users will have to
configure cache LVs after installation or by dropping into a command line.
Also, Anaconda could fail if installing a new OS onto an existing cache LV if
support is not provided.
Anaconda team signed as co-owners of this Change.
The dracut team must provide boot support. If dracut does not provide
support, cache LVs will not be usable as root devices.
* Release engineering: N/A (not a System Wide Change)
* Policies and guidelines: N/A (not a System Wide Change)