in reply to Re^2: Using threads to process multiple files
in thread Using threads to process multiple files
I usually find the there isn't a large difference between one disk read & many reads. The disk read code path is complex and has multiple layers of caching and read-ahead, so it's difficult to generalize. The OS and/or file system will do caching and read-ahead and so will the hardware layers too. (Unfortunately the hardware vendors are a secretive bunch and won't tell us what the disks and controllers get up to!). And that's before you start considering the different file systems, raid setups and controller hardware that you might be using.
tldr; Benchmark to be sure and see what's relevant in your particular case.