v2.7 release note (#4768)

docs/source/release.rst

@@ -5,6 +5,54 @@
 Change Log
 ==========
 
+Release 2.7 - 4/14/2022
+-----------------------
+
+Documentation
+^^^^^^^^^^^^^
+A full-size upgrade of the documentation, with the following significant improvements in the reading experience, practical tutorials, and examples:
+
+* Reorganized the document structure with a new document template. (`Upgraded doc entry <https://nni.readthedocs.io/en/v2.7>`__)
+* Add more friendly tutorials with jupyter notebook.(`New Quick Starts <https://nni.readthedocs.io/en/v2.7/quickstart.html>`__)
+
+Hyper-Parameter Optimization
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+* [Improvement] TPE and random tuners will not generate duplicate hyperparameters anymore.
+* [Improvement] Most Python APIs now have type annotations.
+
+Neural Architecture Search
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+* Jointly search for architecture and hyper-parameters: ValueChoice in evaluator. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/search_space.html#valuechoice>`__)
+* Support composition (transformation) of one or several value choices. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/search_space.html#valuechoice>`__)
+* Enhanced Cell API (``merge_op``, preprocessor, postprocessor). (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/search_space.html#cell>`__)
+* The argument ``depth`` in the ``Repeat`` API allows ValueChoice. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/search_space.html#repeat>`__)
+* Support loading ``state_dict`` between sub-net and super-net. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/others.html#nni.retiarii.utils.original_state_dict_hooks>`__, `example in spos <https://nni.readthedocs.io/en/v2.7/reference/nas/strategy.html#spos>`__)
+* Support BN fine-tuning and evaluation in SPOS example. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/strategy.html#spos>`__)
+* *Experimental* Model hyper-parameter choice. (`doc <https://nni.readthedocs.io/en/v2.7/reference/nas/search_space.html#modelparameterchoice>`__)
+* *Preview* Lightning implementation for Retiarii including DARTS, ENAS, ProxylessNAS and RandomNAS. (`example usage <https://github.com/microsoft/nni/blob/v2.7/test/ut/retiarii/test_oneshot.py>`__)
+* *Preview* A search space hub that contains 10 search spaces. (`code <https://github.com/microsoft/nni/tree/v2.7/nni/retiarii/hub>`__)
+
+Model Compression
+^^^^^^^^^^^^^^^^^
+* Pruning V2 is promoted as default pruning framework, old pruning is legacy and keeps for a few releases.(`doc <https://nni.readthedocs.io/en/v2.7/reference/compression/pruner.html>`__)
+* A new pruning mode ``balance`` is supported in ``LevelPruner``.(`doc <https://nni.readthedocs.io/en/v2.7/reference/compression/pruner.html#level-pruner>`__)
+* Support coarse-grained pruning in ``ADMMPruner``.(`doc <https://nni.readthedocs.io/en/v2.7/reference/compression/pruner.html#admm-pruner>`__)
+* [Improvement] Support more operation types in pruning speedup.
+* [Improvement] Optimize performance of some pruners.
+
+Experiment
+^^^^^^^^^^
+* [Improvement] Experiment.run() no longer stops web portal on return.
+
+Notable Bugfixes
+^^^^^^^^^^^^^^^^
+* Fixed: experiment list could not open experiment with prefix.
+* Fixed: serializer for complex kinds of arguments.
+* Fixed: some typos in code. (thanks @a1trl9 @mrshu)
+* Fixed: dependency issue across layer in pruning speedup. 
+* Fixed: uncheck trial doesn't work bug in the detail table.
+* Fixed: filter name | id bug in the experiment management page.
+
 Release 2.6 - 1/19/2022
 -----------------------