On Mon, Mar 8, 2010 at 10:18 AM, Martin K. Petersen <martin.petersen@xxxxxxxxxx> wrote: >>>>>> "Tejun" == Tejun Heo <tj@xxxxxxxxxx> writes: > > Tejun> The [Windows Vista/7] partitioner seems to be using 1M as the > Tejun> basic alignment unit and offsetting from there if explicitly > Tejun> requested by the drive > > Yep. > > > Tejun> Please note that hdparm is misreporting the alignment offset. It > Tejun> should be reporting 512 instead of 256 for offset-by-one drives. > > Already fixed. Your hdparm must be old. > > > > Tejun> Partitioners maybe should only align partitions which will be > Tejun> used by Linux and default to the traditional layout for others > Tejun> while allowing explicit override. > > I don't think we take the partition type into account. Karel? > > > Tejun> Reportedly, commonly used partitioners aren't ready to handle > Tejun> drives larger than 2 TiB in any configuration and alignment isn't > Tejun> done properly for drives with 4 KiB physical sectors. 4 KiB > Tejun> logical sector support is broken in both the kernel > > Huh, what? My homedir is on a 4KiB LBS/PBS drive and has been for ~2 > years. > > > Tejun> (need more details and probably a whole section on partitioner > Tejun> behaviors) > > I'm Cc:'ing Karel Zak and Jim Meyering who have been doing all the > alignment work for fdisk and parted respectively. Karel, Jim: The full > writeup is here: > > http://ata.wiki.kernel.org/index.php/ATA_4_KiB_sector_issues > > It'd be great if you guys could share what you have been doing to the > tooling. I've been keeping track of all the pieces in play, have coordinated with kzak and jim, and have a summary that offers some amount of macro detail (at the end I touch on parted and fdisk): http://people.redhat.com/msnitzer/docs/io-limits.txt -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
