This is what I remember: If you disable journalling, running fsck after a crash will (be required and) take longer. Certainly not a good idea to have an extra wait after the cluster loses power and is being restarted, etc.
On Tue, Jul 9, 2013 at 7:42 AM, Chris Embree <cemb...@gmail.com> wrote: > Hey Hadoop smart folks.... > > I have a tendency to seek optimum performance given my understanding, so > that led to me "brilliant" decision. We settled on EXT4 for our underlying > FS for HDFS. Greedy for speed I thought, let's turn the journal off and > gain the speed benefits. After all, I have 3 copies of the data. > > How much does this bother you, given we have a 21 node prod and only 10 node > dev cluster. > > I'm embarrassed to say I did not capture good pre and post change I/O. In > my simple brain, not writing to journal just screams improved I/O. > > Don't be shy, tell me how badly I have done bad things. (I originally said > "screwed the pooch" but I reconsidered our > USA audience. ;) > > If I'm not incredibly wrong, should we consider higher speed (less safe) > file systems? > > Correct/support my thinking. > Chris -- Harsh J
