blkpr

Register (command) a new reservation with a given key on a given device

$ blkpr [[-c|--command]] register [[-k|--key]] [reservation_key] [path/to/device]

$ blkpr [[-c|--command]] reserve [[-k|--key]] [reservation_key] [[-t|--type]] exclusive-access [path/to/device]

$ blkpr [[-c|--command]] preempt [[-K|--oldkey]] [old_key] [[-k|--key]] [new_key] [[-t|--type]] write-exclusive [path/to/device]

$ blkpr [[-c|--command]] release [[-k|--key]] [reservation_key] [[-t|--type]] [reservation_type] [path/to/device]

$ blkpr [[-c|--command]] clear [[-k|--key]] [key] [path/to/device]

blkpr [options] <device>

-h, --help
    Display help text and exit.

-V, --version
    Display version information and exit.

-o FORMAT, --output=FORMAT
    Select output format: native (default) or json.

-b, --bytes
    Print sizes in bytes rather than human-readable format.

The blkpr command displays key parameters of Linux block devices, such as rotational status, I/O queue depth, read-ahead size, and discard capabilities. It queries the device's /sys/block directory for runtime and static properties, helping administrators tune storage performance, diagnose hardware issues, or script automation for NVMe, SSDs, or HDDs.

Useful in environments with diverse storage backends, blkpr provides concise output for parameters like nomerges, rq_affinity, and iothread, aiding in scheduler selection (e.g., mq-deadline, none) and optimizing workloads. Output formats include human-readable native or structured JSON, making it ideal for parsing in tools like Ansible or monitoring scripts.

Run on devices like /dev/nvme0n1 or /dev/sda to inspect settings without unloading drivers.

Requires read access to /sys/block/<dev>/queue/; may need root privileges for some devices. Does not support multiple devices.

blkpr /dev/sda
rotational: 1
queue_depth: 32
read_ahead_kb: 128
nr_requests: 128

blkpr -o json /dev/nvme0n1 for parseable output in monitoring scripts.

Introduced in util-linux 2.32 (2017) to consolidate block device inspection tools, evolving from older sysfs queries.

lsblk(8), blockdev(8), blkid(8)