As the storage wars continue, the debate of ZFS vs LVM continues. I have been dealing with ZFS heavily for about a year now and just don't see it as a viable file system for a lot of applications that would otherwise benefit from its feature set.
Specifically "thin provisioned volumes" for virtual machines or iscsi luns. Yes, ZFS zvols do support thin provisioning and the API is basically correct. Unfortunately, the implementation of ZFS is too resource intensive for much hungrier applications. LVM is much more light weight and has better performance in applications that manage their own journalling and data integrity (like a database). LVM has recently gained "thin provisioning" of volumes, but its kind of broken. You create a "thin pool" as an LVM volume and then sub-allocate LVM volumes out of that. So, you have the volume group, the "thin pool" allocated out of the volume group, and the volumes allocated out of the thin pool. I am not sure if this even makes sense. It is conceptually no different than allocating a volume out of a volume group, putting a file system on it (ETX2, say) and then putting a sparse file on it. The EXT2 file system is performing the function of the "thin pool" code. I think its kind of bogus. Any opinions? _______________________________________________ Discuss mailing list [email protected] http://lists.blu.org/mailman/listinfo/discuss
