Hi, Could someone explain what vertex and message combiners do exactly? Which vertices/messages do they combine?
Do they combine vertices/messages of the same partition? If yes, how are messages originating from one partition divided back to different distention partitions (because not necessarily the destination vertices are in the same partition)? Is this done by Giraph automatically, or should something be implemented to take care of that? If not, is there any interface that supports such kind of functionality (combining messages outgoing from one partition)? Thanks!
