On Thu, Sep 30 2010 at 1:07pm -0400, Eric Sandeen <sandeen@xxxxxxxxxx> wrote: > On 09/30/2010 11:30 AM, Ted Ts'o wrote: > > On Tue, Sep 28, 2010 at 04:36:42PM -0500, Eric Sandeen wrote: > >> Ok, then it sounds like mkfs.ext4's refusal to make fs blocksize less > >> than device physical sectorsize without -F is broken, and that should > >> be removed. I'd say issue a warning in the case but if there's a 16k > >> physical device maybe there's no point in warning either? > > > > If the device physical sectorsize is that big, should we perhaps use > > that as a hint to align writes to that blocks aligned with that > > physical sectorsize? Right now we use the optimal I/O size, but if > > the optimal I/O size is not specified and the physical sectorsize is, > > I can't keep track of all the parameters, is it ever true that optimal > I/O size isn't specified? Yes optimal_io_size may be 0. But minimum_io_size will always be scaled up to at least match physical_block_size. In any case: this 1MB physical_block_size device, which started this thread, also has 1MB for both minimum_io_size and optimal_io_size. Mike -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html