Nick Piggin wrote:
I think 32MB is too much. You incur latency and lose
scheduling grainularity. I bet returns start diminishing
pretty quickly after 1MB or so.
See my reply to Bart.
Also, it is not the driver's responsibility to do anything but export the hardware maximums.
It's up to the sysadmin to choose a disk scheduling policy they like, which implies that a _scheduler_, not each individual driver, should place policy limitations on max_sectors.