Merge pull request #958 from martinsumner/develop-2.9

Develop 2.9

doc/Release 2.9 Series - Overview.md

@@ -147,6 +147,12 @@ The RC4 changes only have an impact on the behaviour of Riak when used with a le
 
 - The riak_kv_leveled_backend will support v1 objects only, the riak_kv_vnode will never try to write an object as v0 into leveled.
 
+#### Release 2.9.0 RC5
+
+The primary RC5 change is again leveled related.  It was discovered in handoff scenarios in a leveled backend, Riak consumed much more memory than expected.  This was caused by "switched" Level 0 files in the Penciller.  These files have a small memory footprint when garbage collected, but a large footprint uncollected - there is a legacy of all the data being on the LoopState in the `starting` state (but not the `reader` state).  Each file process now does `garbage_collect/1` on self at the point of the switch to free this memory immediately.
+
+There is also a small fix to poolboy to prevent a crash log from appearing on shutdown.
+
 #### Transition Configuration Guidance
 
 This section contains some initial notes to assist with planning and configuration for Transition of pre-2.9 releases to 2.9: