On 11/06/2014 07:25 PM, Martin K. Petersen wrote: >>>>>> "Boaz" == Boaz Harrosh <boaz@xxxxxxxxxxxxx> writes: > > Boaz, > > Boaz> Note that blk_queue_physical_block_size() also trashes io_min, but > Boaz> we can leave this one to be 512. io_min as opposed to > Boaz> physical_block_size will actually change Kernel behavior > >>> Care to elaborate? > > I wanted you to elaborate on how io_min changes kernel behavior. > OK You are correct. io_min changes behavior of Kernel in exactly the same way as physical_block_size. Through the call to queue_limit_alignment_offset() inside add_partition() by setting hd_struct->alignment_offset I do not know why I thought that only io_min does that, I can see now that both effect the Kernel the same way. Which scares me a bit. Will I have problems? <> > > It really sounds like either your fdisk is way too old or you are > running it in DOS compat mode. > > I don't have a fundamental issue reporting pbs of 4K. But if you are > only doing it to force a certain partition alignment then it sounds like > a kernel fix for a userland problem. > > I've CC:ed Karel who can comment on fdisk partition alignment issues. > Thanks Martin. I agree, we should not fix user-mode problems. Please see the other email with the exact numbers I get from fdisk. It looks like when everything is 512 like default it would not align my partitions, but with the 4k-phisical thing it would. What is the expected behavior we want? Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
