General Linux filesystem tuning
Regardless of what filesystem you choose, there are some general Linux tuning operations that apply.
Read-ahead
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 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 (covered in Chapter 3, Database Hardware Benchmarking) jump upwards. This corresponds to a big increase in large sequential I/O operations in PostgreSQL too, including...
