> If there is a way to tell this disk is 4K sectored > drive, SD can inform > ZFS to make all I/O 4K aligned. > > We will have those functions you mentioned in SD to > support flash disk > very soon. Will not be hard to support this hard > drive in that manner as > well. > > Anyone has a disk for us to try? > Roger >
If I understand correctly, the drives listed on http://www.wdc.com/wdproducts/library/SpecSheet/ENG/2879-701278.pdf with model numbers ending in PVT are SATA drives with 4K sectors. They probably are backwards compatible, but I would hope they might be able to identify themselves as using 4K sectors as described below. Note: I've not used nor seen one, and haven't checked availability. http://www.idema.org/_smartsite/modules/local/data_file/show_file.php?cmd=download&data_file_id=1261 says (for ATA/ATAPI drives): >Because ATA/ATAPI-7 maintains full backward compatibility with previous >>standards for 4K drives there are no new commands, modes, or set features >>settings to enable 4K support. Drives with multiple LBA’s per physical sector >set >Identify Device word 106 bit 13 to 1. The number of LBA’s per physical >sector is >indicated in Identify Device word 106 bits 0-3. For 4K sectors the >value is set to 3 >(23=8 LBA’s per Sector) while with SCSI, if I understand correctly, a READ CAPACITY command returns the LBA of the highest block as well as the block size. disclaimer: as a home user, I don't have enough of a hardware budget for this to matter to me any time soon, while in any other capacity, I make no claim of controlling anyone else's money. However, by the time I have to worry about new standards, I hope the support for them is reasonably mature. Therefore, I poke and prod and ask questions and and do a little research and pass it on... -- This message posted from opensolaris.org _______________________________________________ storage-discuss mailing list storage-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/storage-discuss
