General options

Understand the general options for Ceph Block Devices.

Table 1 lists the different default options for Ceph Block Device configuration.

Table 1. Ceph Block Device general options
Option	Description	Type	Default
`rbd_clone_copy_on_read`	When set to `true`, copy-on-read cloning is enabled.	Boolean	`false`
`rbd_concurrent_management_ops`	The maximum number of concurrent management operations in flight (for example, deleting or resizing an image).	Integer	`10`
`rbd_enable_alloc_hint`	If `true`, allocation hinting is enabled, and the block device will issue a hint to the OSD back end to indicate the expected size object.	Boolean	`true`
`rbd_non_blocking_aio`	If `true`, Ceph will process block device asynchronous I/O operations from a worker thread to prevent blocking.	Boolean	`true`
`rbd_op_thread_timeout`	The timeout (in seconds) for block device operation threads.	Integer	`60`
`rbd_op_threads`	The number of block device operation threads. Warning: Do not change the default value of `rbd_op_threads` because setting it to a number higher than `1` might cause data corruption.	Integer	`1`
`rbd_request_timed_out_seconds`	The number of seconds before a maintenance request times out.	Integer	`30`
`rbd_skip_partial_discard`	If `true`, the block device will skip zeroing a range when trying to discard a range inside an object.	Boolean	`true`
`rbd_tracing`	Set this option to `true` to enable the Linux Trace Toolkit Next Generation User Space Tracer (LTTng-UST) tracepoints. For more information, see Tracing RADOS Block Device (RBD) Workloads with the RBD Replay Feature within the Red Hat Customer Portal.	Boolean	`false`
`rbd_validate_names`	Set this option to `true` to validate image specifications.	Boolean	`true`
`rbd_validate_pool`	Set this option to `true` to validate empty pools for RBD compatibility.	Boolean	`true`