On 7 June 2012 12:59, Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> wrote: > On 6/6/2012 10:41 PM, Igor M Podlesny wrote: >> They try, for sure, but try is still a try. For e. g., you pvmove'd >> your LVM with XFS from one RAID to another one having different >> "layout", things can just stop working well all of the sudden. > > Filesystems that have zero awareness of the storage geometry have poor > performance on striped RAID devices. XFS has excellent performance on > striped RAID specifically due to this awareness. Now you describe this And Btrfs is way faster (~ 30 %) on single sustained 22 GiB reading — http://poige.livejournal.com/560643.html XFS is excellent but for parallel I/O mainly due to its multiple allocation groups, not "RAID awareness" — EXT3/4 can be formatted adjusted to RAID's layout just as XFS, in case you didn't know it. > strength as a weakness due to a volume portability corner case no SA in > his right mind would attempt. > > The proper way to do this is to perform an xfsdump of the filesystem to > a file, create a new XFS with the proper stripe geometry in the new > storage location (which takes all of 1 second BTW), then xfsrestore the > dump file. Damn the proper way, Stan, if it's inconvenient one, and some better results can be automagically achieved using another way. Which one is more proper then? ) I see no point in arguing just to argue. I see no drawbacks in chunks not limited to 2^n, since at least it doesn't prohibit 2^n as well. So, there's no point really. -- -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
