Is it possible to upgrade ext4 without losing existing data ? Thanks
On Fri, Nov 11, 2011 at 2:24 PM, Edward Capriolo <edlinuxg...@gmail.com>wrote: > On Fri, Nov 11, 2011 at 4:42 PM, Otis Gospodnetic < > otis_gospodne...@yahoo.com> wrote: > > > Hello, > > > > I was wondering if anyone has done an experiment with HBase or HDFS/MR > > where machines in the cluster have heterogeneous underlying file systems? > > e.g., > > * 10 nodes with xfs > > * 10 nodes with ext3 > > * 10 nodes with ext4 > > > > The goal being comparing performance of MapReduce jobs reading from and > > writing to HBase (or just HDFS). > > > > > > And does anyone have any reason to believe doing the above would be super > > risky and cause data loss? > > > > Thanks, > > Otis > > ---- > > Sematext :: http://sematext.com/ :: Solr - Lucene - Nutch > > Lucene ecosystem search :: http://search-lucene.com/ > > > Since Hadoop abstracts you from the filesystem guts the underlying file > system chosen can be mixed and matched. you can even mix and match the > disks on a single machine. > > I have found that ext3 performance gets noticeably poor as disks gets full. > I captured system vitals from a before and after ext3 to ext4 upgrade. > > > http://www.edwardcapriolo.com/roller/edwardcapriolo/entry/a_great_reason_to_use > > Also if you want to get the most out of your disks read this: > > > http://allthingshadoop.com/2011/05/20/faster-datanodes-with-less-wait-io-using-df-instead-of-du/ > > XFS should is usually described as on par or slightly better then ext4. > However anecdotally most hardcore sysadmins I know can account for one XFS > "i lost my super block" stories :) >
