I could be an offset defined. Could you post following files? /sys/block/sdd/queue/optimal_io_size /sys/block/sdd/queue/minimum_io_size /sys/block/sdd/alignment_offset /sys/block/sdd/queue/physical_block_size /sys/block/sdd/queue/logical_block_size
Toni Mas Missatge de Sergey Spiridonov <s...@s73.work> del dia dc., 4 de des. 2019 a les 13:30: > > Hi all > > I am trying to partition 14TB HDD and get the following problem with an > alignment: > > # hdparam -I /dev/sdd tells that > > Logical Sector size: 512 bytes > Physical Sector size: 4096 bytes > > > # parted -a opt /dev/sdd > > (parted) mkpart primary 0% 100% > ... > > (parted) print > > Number Start End Size File system Name Flags > 1 33,6MB 14,0TB 14,0TB primary > > Now checking alignment: > > (parted) align-check opt > 1 1 aligned > > > So far, so good. Now let's look at the same disk with fdisk: > > # fdisk /dev/sdd > > : p > > Disk /dev/sdd: 12,8 TiB, 14000519643136 bytes, 27344764928 sectors > Disk model: IB-366StU3+B > Units: sectors of 1 * 512 = 512 bytes > Sector size (logical/physical): 512 bytes / 4096 bytes > I/O size (minimum/optimal): 4096 bytes / 33553920 bytes > Disklabel type: gpt > Disk identifier: 82DD924B-BF0E-40FF-9037-1FD4E7307D26 > > Device Start End Sectors Size Type > /dev/sdd1 65535 27344740889 27344675355 12,8T Linux filesystem > > Partition 1 does not start on physical sector boundary. > > > What? Why? > > > man parted tells that > > optimal > Use optimum alignment as given by the disk > topology in‐ formation. This aligns to a > multiple of the physical block size in a way that > guarantees optimal performance > > > 1. Probably parted detected physical sector size as 512 > instead of 4096? Why? > > 2. Even if parted thinks that physical sector is 512 instead of > 4096, why start from 65535 and not from 65536? What is the logic > behind? How using odd multiplier can improve performance? > > Is it a bug in parted or I am missing something? > -- > Best regards, Sergey Spiridonov > > >