basho/riak_core — pull request #257 by jtuple (2012-12-07 18:09:01+00:00)
Title: Enable riak_core apps to provide a health_check callback

This pull-request enables applications built on riak_core to provide {health_check, MFA} as an option during registration. The provided health check will then be passed on to `riak_core_node_watcher:service_up` when the service is marked as up. This enables riak_core applications to take advantage of the new health check functionality added to `riak_core_node_watcher` in #240

This pull-request provides the basis for a sister pull-request to riak_kv that adds a health check to Riak K/V.

This PR also includes a commit that changes certain `riak_core_vnode_manager` API calls to be more efficient by directly accessing a protected ETS table when possible, rather than always using calls to the `riak_core_vnode_manager`. This fixes a long standing issue with the vnode manager, and is a necessary change to make the health check added to Riak K/V efficient.