Damien, > Any idea why the io_opt limit is not set to the physical block size > when the drive does not report an optimal transfer length ? Would it > be bad to set that value instead of leaving it to 0 ? The original intent was that io_opt was a weak heuristic for something being a RAID device. Regular disk drives didn't report it. These days that distinction probably isn't relevant. However, before we entertain departing from the historic io_opt behavior, I am a bit puzzled by the fact that you have a device that reports io_opt as 512 bytes. What kind of device performs best when each I/O is limited to a single logical block? -- Martin K. Petersen Oracle Linux Engineering -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
