The first parameter you should tune on any Linux installation is device read-ahead. When doing sequential reads that seem to be moving forward, this feature results in Linux asking for blocks from the disk ahead of the application requesting them.
This is the key to reaching full read performance from today's faster drives. The usual symptom of insufficient read-ahead is noting that write speed to a disk is faster than its read speed. The impact is not subtle; proper read-ahead can easily result in a 100% or larger increase in sequential read performance. It is the most effective filesystem adjustment to make on Linux if you want to see benchmarks like the bonnie++ read speed jump upwards. This corresponds to a big increase in ...
