In my case (Hammer 0.94.5) I see actually the proper alignment made by ceph-disk. Thing is that fdisk is not able to see GPT partitions: root@slpeah001:[~]:# fdisk -l /dev/sdf Disk /dev/sdf: 4000.8 GB, 4000787030016 bytes, 7814037168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdf1 1 4294967295 2147483647+ ee GPT root@slpeah001:[~]:# gdisk -l /dev/sdf GPT fdisk (gdisk) version 0.8.6 Partition table scan: MBR: protective BSD: not present APM: not present GPT: present Found valid GPT with protective MBR; using GPT. Disk /dev/sdf: 7814037168 sectors, 3.6 TiB Logical sector size: 512 bytes Disk identifier (GUID): E1063D97-3EFF-4F81-A08F-81D069625677 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 7814037134 Partitions will be aligned on 2048-sector boundaries Total free space is 2014 sectors (1007.0 KiB) Number Start (sector) End (sector) Size Code Name 1 2048 7814037134 3.6 TiB FFFF ceph data So I think ceph-disk does things right... But before I use ceph-disk I create an empty GPT with gdisk. 2016-02-23 13:49 GMT+08:00 Loic Dachary <loic@xxxxxxxxxxx>: > Here it is http://tracker.ceph.com/issues/14842 > > On 23/02/2016 12:24, Somnath Roy wrote: >> eph-deploy is creating data partition from sector 1 ignoring what sgdisk is recommending (256 in my disk). Basically, it should be aligned with physical sector size (reported in /sys/block/<device>/queue/physical_block_size). In my case it is 16K physical and 4K logical...256 is perfectly fine as sgdisk/fdisk internally decides. >>> Disk performance will be severely impacted because of partitioning this way from ceph-deploy , > > -- > Loïc Dachary, Artisan Logiciel Libre > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
