Fix dedup/compression description in doc

In the capabilities section of capabilities_and_extra_specs.rst,
the description of dedupe and compression all say that drivers
cannot report to the scheduler both support and non-support,
like [True, False].

But since Mitaka, this kind of specifying is allowed.
So change the doc contents to fit the actual logic.

Change-Id: Ie871abc49bd1bc58566111f85d89228046865b5c
Closes-Bug: #1621707
This commit is contained in:
zengyingzhe 2016-09-12 15:31:20 +08:00
parent 29c05e72f5
commit 832712f2dc

View File

@ -93,21 +93,27 @@ be created.
* `dedupe` - indicates that a backend/pool can provide shares using some
deduplication technology. The default value of the dedupe capability (if a
driver doesn't report it) is False. Drivers cannot report to the scheduler
that they support both dedupe and non-deduped share. For each pool it's
either always on or always off. Administrators can make a share type use
deduplication by setting this extra-spec to '<is> True'. Administrators can
prevent a share type from using deduplication by setting this extra-spec to
'<is> False'. Added in Liberty.
driver doesn't report it) is False. In Liberty, drivers cannot report to the
scheduler that they support both dedupe and non-deduped share. For each pool
it's either always on or always off, even if the drivers can technically
support both dedupe and non-deduped in a pool. Since Mitaka, the logic is
changed to allow a driver to report dedupe=[True, False] if it can support
both dedupe and non-deduped in a pool. Administrators can make a share type
use deduplication by setting this extra-spec to '<is> True'. Administrators
can prevent a share type from using deduplication by setting this extra-spec
to '<is> False'. Added in Liberty.
* `compression` - indicates that a backend/pool can provide shares using some
compression technology. The default value of the compression capability (if a
driver doesn't report it) is False. Drivers cannot report to the scheduler
that they support both compression and non-compression. For each pool it's
either always on or always off. Administrators can make a share type use
compression by setting this extra-spec to '<is> True'. Administrators can
prevent a share type from using compression by setting this extra-spec to
'<is> False'. Added in Liberty.
driver doesn't report it) is False. In Liberty, drivers cannot report to the
scheduler that they support both compression and non-compression. For each
pool it's either always on or always off, even if the drivers can technically
support both compression and non-compression in a pool. Since Mitaka, the
logic is changed to allow a driver to report compression=[True, False] if it
can support both compression and non-compression in a pool. Administrators
can make a share type use compression by setting this extra-spec to
'<is> True'. Administrators can prevent a share type from using compression
by setting this extra-spec to '<is> False'. Added in Liberty.
* `thin_provisioning` - shares will not be space guaranteed and
overprovisioning will be enabled. This capability defaults to False.