Update the changelog to prepare for the next release.

Changelog

=========

Upcoming release

----------------

v16.08: iSCSI target, NVMf maturity

-----------------------------------

This release adds a userspace iSCSI target. The iSCSI target is capable of exporting

NVMe devices over a network using the iSCSI protocol. The application is located

in app/iscsi_tgt and a documented configuration file can be found at etc/spdk/spdk.conf.in.

- NVMe

  - The Weighted Round Robin arbitration method is now supported. This allows

    the user to specify different priorities on a per-I/O-queue basis.  To

    enable WRR, set the `arb_mechanism` field during `spdk_nvme_probe()`.

  - A simplified "Hello World" example was added to show the proper way to use

    the NVMe library API; see `examples/nvme/hello_world/hello_world.c`.

- NVMe over Fabrics

This release also significantly improves the existing NVMe over Fabrics target.

  - The configuration file format was changed, which will require updates to

    any existing nvmf.conf files (see `etc/spdk/nvmf.conf.in`):

    - `SubsystemGroup` was renamed to `Subsystem`.

    - `nvmf_tgt` was updated to correctly recognize NQN (NVMe Qualified Names)

      when naming subsystems.  The default node name was changed to reflect this;

      it is now "nqn.2016-06.io.spdk".

    - `Port` and `Host` sections were merged into the `Subsystem` section

    - Global options to control max queue depth, number of queues, max I/O

      size, and max in-capsule data size were added.

    - The Nvme section was removed. Now a list of devices is specified by

      bus/device/function directly in the Subsystem section.

    - Subsystems now have a Mode, which can be Direct or Virtual. This is an attempt

      to future-proof the interface, so the only mode supported by this release

      is "Direct".

  - Many bug fixes and cleanups were applied to the `nvmf_tgt` app and library.

  - The target now supports discovery.

This release also adds one new feature and provides some better examples and tools

for the NVMe driver.

  - The Weighted Round Robin arbitration method is now supported. This allows

    the user to specify different priorities on a per-I/O-queue basis.  To

    enable WRR, set the `arb_mechanism` field during `spdk_nvme_probe()`.

  - A simplified "Hello World" example was added to show the proper way to use

    the NVMe library API; see `examples/nvme/hello_world/hello_world.c`.

  - A test for measuring software overhead was added. See `test/lib/nvme/overhead`.

v16.06: NVMf userspace target

-----------------------------