Adds documentation how to change default rbd object size. With the
previous option `--order` it was easy to guess the config name for the
default value, with the current option name `--object-size` thats hard
to guess.
Also extends the documentation for rbd_default_order to include
* how object-size is derived from the configured value
* allowed range of the value
In the first version of this commit I also added min and max for this
parameter (12/25, matching the object size range in `man 8
rbd`/Striping/object-size), but this made some tests fail, since some
seem to set values outside this range (and probably are fine since
included for some time already). To have this a doc-change only, I
removed the range.
Signed-off-by: Mara Sophie Grosch <littlefox@lf-net.org>
nearest power of two; if no suffix is given, unit B is assumed. The default
object size is 4M, smallest is 4K and maximum is 32M.
+ The default value can be changed with the configuration option ``rbd_default_order``,
+ which takes a power of two (default object size is ``2 ^ rbd_default_order``).
+
.. option:: --stripe-unit size-in-B/K/M
Specifies the stripe unit size in B/K/M. If no suffix is given, unit B is
.. confval:: rbd_compression_hint
.. confval:: rbd_read_from_replica_policy
+.. confval:: rbd_default_order
Cache Settings
=======================
type: uint
level: advanced
desc: default order (data block object size) for new images
+ long_desc: This configures the default object size for new images. The value is used as a
+ power of two, meaning ``default_object_size = 2 ^ rbd_default_order``. Configure a value
+ between 12 and 25 (inclusive), translating to 4KiB lower and 32MiB upper limit.
default: 22
services:
- rbd