| What: /sys/block/dm-<num>/dm/name |
| Date: January 2009 |
| KernelVersion: 2.6.29 |
| Contact: dm-devel@redhat.com |
| Description: Device-mapper device name. |
| Read-only string containing mapped device name. |
| Users: util-linux, device-mapper udev rules |
| |
| What: /sys/block/dm-<num>/dm/uuid |
| Date: January 2009 |
| KernelVersion: 2.6.29 |
| Contact: dm-devel@redhat.com |
| Description: Device-mapper device UUID. |
| Read-only string containing DM-UUID or empty string |
| if DM-UUID is not set. |
| Users: util-linux, device-mapper udev rules |
| |
| What: /sys/block/dm-<num>/dm/suspended |
| Date: June 2009 |
| KernelVersion: 2.6.31 |
| Contact: dm-devel@redhat.com |
| Description: Device-mapper device suspend state. |
| Contains the value 1 while the device is suspended. |
| Otherwise it contains 0. Read-only attribute. |
| Users: util-linux, device-mapper udev rules |
| |
| What: /sys/block/dm-<num>/dm/rq_based_seq_io_merge_deadline |
| Date: March 2015 |
| KernelVersion: 4.1 |
| Contact: dm-devel@redhat.com |
| Description: Allow control over how long a request that is a |
| reasonable merge candidate can be queued on the request |
| queue. The resolution of this deadline is in |
| microseconds (ranging from 1 to 100000 usecs). |
| Setting this attribute to 0 (the default) will disable |
| request-based DM's merge heuristic and associated extra |
| accounting. This attribute is not applicable to |
| bio-based DM devices so it will only ever report 0 for |
| them. |
| |
| What: /sys/block/dm-<num>/dm/use_blk_mq |
| Date: March 2015 |
| KernelVersion: 4.1 |
| Contact: dm-devel@redhat.com |
| Description: Request-based Device-mapper blk-mq I/O path mode. |
| Contains the value 1 if the device is using blk-mq. |
| Otherwise it contains 0. Read-only attribute. |
