On 2010-Oct-06 05:59:06 +0800, Michael DeMan <sola...@deman.com> wrote: >Another annoying thing with the whole 4K sector size, is what happens >when you need to replace drives next year, or the year after?
About the only mitigation needed is to ensure that any partitioning is based on multiples of 4KB. > Does >anybody know if there any vendors that are shipping 4K sector drives >that have a jumper option to make them 512 size? This would require a low-level re-format and would significantly reduce the available space if it was possible at all. > WD has a jumper, >but is there explicitly to work with WindowsXP, and is not a real way >to dumb down the drive to 512. All it does is offset the sector numbers by 1 so that sector 63 becomes physical sector 64 (a multiple of 4KB). > I would presume that any vendor that >is shipping 4K sector size drives now, with a jumper to make it >'real' 512, would be supporting that over the long run? I would be very surprised if any vendor shipped a drive that could be jumpered to "real" 512 bytes. The best you are going to get is jumpered to logical 512 bytes and maybe a 1-sector offset (needed for WindozeXP only). These jumpers will probably last as long as the 8GB jumpers that were needed by old BIOS code. (Eg BIOS boots using simulated 512-byte sectors and then the OS tells the drive to switch to native mode). It's unfortunate that Sun didn't bite the bullet several decades ago and provide support for block sizes other than 512-bytes instead of getting custom firmware for their CD drives to make them provide 512-byte logical blocks for 2KB CD-ROMs. It's even more idiotic of WD to sell a drive with 4KB sectors but not provide any way for an OS to identify those drives and perform 4KB aligned I/O. -- Peter Jeremy _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
