On 07/14/2010 01:39 PM, Sven Eschenberg wrote: > Is there any 'easy' way to access this information. specifically I am > interested, why md would report a 6144 sectors alignment on my 4 disk > raid5 with 512 kb chunks instead of 3072. Values are in in sysfs also, I am just using topology ioctl which is simpler. sysfs interface --------------- /sys/block/<disk>/alignment_offset /sys/block/<disk>/<partition>/alignment_offset /sys/block/<disk>/queue/physical_block_size /sys/block/<disk>/queue/logical_block_size /sys/block/<disk>/queue/minimum_io_size /sys/block/<disk>/queue/optimal_io_size cryptsetup uses minimal/optimal io_size and alignment value to calculate payload offset. A lot of info here: http://people.redhat.com/msnitzer/docs/io-limits.txt https://ata.wiki.kernel.org/index.php/ATA_4_KiB_sector_issues Milan _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
