doc: draft notes for jewel

[liewegas]

No description provided.

[dillaman]

@liewegas Github isn't allowing inline comments:

Major changes since Infernalis:

• The exclusive-lock, object-map, fast-diff, and journaling features can be enabled or disabled dynamically. The deep-flatten can be disabled dynamically but not re-enabled.
• The RBD CLI has been rewritten to provide command-specific help and full bash completion support.
• RBD snapshots can now be renamed.

Minor changes since Infernalis (worth mentioning):

• The default RBD image features for new images have been updated to enable the following: exclusive lock, object map, fast-diff, and deep-flatten. These features are not currently supported by the RBD kernel driver nor older RBD clients. These features can be disabled on a per-image basis via the RBD CLI or the default features can be updated to the pre-Jewel setting by adding the following to the client section of the Ceph configuration file:
  rbd default features = 1
• The rbd legacy image format (version 1) is deprecated with the Jewel release.

[jdurgin]

only c++ applications, right?

[dillaman]

Correct -- it was in buffer.h

[jdurgin]

"multiple MDS servers" - is active/standy not considered stable?

[jdurgin]

There is new support for asynchronous replication

perhaps add "(mirroring)" to introduce the term there, and mention the new rbd-mirror daemon

[theanalyst]

github doesst seem to allow inline comments on this changeset.. on RGW:
The new multitenancy infrastructure improves compatibility with Swift (which has a provide namespace of containers for each tenant). -> (which provides ...)