Re: what to get with 20K

Latency is going to suffer with larger stripe sizes. The is simply because the head has to read the full stripe before moving onto the next batch of sectors. Large stripes are typically used where you need increased throughput on large linear reads.

If you need increased latency, which typically benefits smaller non-sequential reads, you would opt for a lower stripe size.

Ideally, if you know you will be doing large sequential reads with a large stripe size it helps to align the file system block size. With read ahead and a large cache it's not such a big deal, but you can eek out some nice performance if you plan accordingly and known the data content.