1 What: /sys/block/dm-<num>/dm/name 2 Date: January 2009 3 KernelVersion: 2.6.29 4 Contact: dm-devel@redhat.com 5 Description: Device-mapper device name. 6 Read-only string containing mapped device name. 7 Users: util-linux, device-mapper udev rules 8 9 What: /sys/block/dm-<num>/dm/uuid 10 Date: January 2009 11 KernelVersion: 2.6.29 12 Contact: dm-devel@redhat.com 13 Description: Device-mapper device UUID. 14 Read-only string containing DM-UUID or empty string 15 if DM-UUID is not set. 16 Users: util-linux, device-mapper udev rules 17 18 What: /sys/block/dm-<num>/dm/suspended 19 Date: June 2009 20 KernelVersion: 2.6.31 21 Contact: dm-devel@redhat.com 22 Description: Device-mapper device suspend state. 23 Contains the value 1 while the device is suspended. 24 Otherwise it contains 0. Read-only attribute. 25 Users: util-linux, device-mapper udev rules 26 27 What: /sys/block/dm-<num>/dm/rq_based_seq_io_merge_deadline 28 Date: March 2015 29 KernelVersion: 4.1 30 Contact: dm-devel@redhat.com 31 Description: Allow control over how long a request that is a 32 reasonable merge candidate can be queued on the request 33 queue. The resolution of this deadline is in 34 microseconds (ranging from 1 to 100000 usecs). 35 Setting this attribute to 0 (the default) will disable 36 request-based DM's merge heuristic and associated extra 37 accounting. This attribute is not applicable to 38 bio-based DM devices so it will only ever report 0 for 39 them. 40 41 What: /sys/block/dm-<num>/dm/use_blk_mq 42 Date: March 2015 43 KernelVersion: 4.1 44 Contact: dm-devel@redhat.com 45 Description: Request-based Device-mapper blk-mq I/O path mode. 46 Contains the value 1 if the device is using blk-mq. 47 Otherwise it contains 0. Read-only attribute.
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.