On Mon 23-07-12 22:21:46, Mel Gorman wrote: > Configuration: global-dhp__io-dbench4-async-ext3 > Result: http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__io-dbench4-async-ext3 > Benchmarks: dbench4 > > Summary > ======= > > In general there was a massive drop in throughput after 3.0. Very broadly > speaking it looks like the Read operation got faster but at the cost of > a big regression in the Flush operation. Mel, I had a look into this and it's actually very likely only a configuration issue. In 3.1 ext3 started to default to enabled barriers (barrier=1 in mount options) which is a safer but slower choice. When I set barriers explicitely, I see no performance difference for dbench4 between 3.0 and 3.1. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>