On Tue, 18 Oct 2011, Emmanuel Dreyfus wrote: > As I understand, at VFS level, VOP_STRATEGY(9) is used for I/O to block > devices. Where does that name comes from?
Block devices use the `strategy()' routines to schedule operations because, unlike character devices which typically immediately post the write opertion to the hardware, they used to go through disksort() so the elevator algorithm could be used to optimize disk access. Hence the strategy() routine did not necessarily start the I/O operation, it would usually add it to a work queue. Eduardo
