geotrellis/geotrellis — pull request #446 by joshmarcus (2013-04-11 15:45:27+00:00)
Title: Enable dispatch of operations to a cluster.

This pull request has a wide variety of commits that came up in the process of working through an example of executing a distributed operation through a cluster (associated with the akka cluster functionality).

The changes include:
-- Update development remoting experiment to use a cluster.
-- Make GeoTrellis actor system a singleton. This commit turns the GeoTrellis akka actor system into a singleton for purposes of the clustering mechanism. The actor system is given a single name ("GeoTrellis") and the tests are changed to no longer create many servers. The TestServer class is removed entirely, and the tests are updated to import from testutils.
-- Change return type of GetHistogram to return FastMapHistogram. …
Because GetHistogram was returning Histogram and not FastMapHistogram,
we could not modify the settings of the operation (the thoroughput limit).
-- Make a variety of classes serializable.
-- Update akka version to 2.1.2.
-- Add LoadUncachedTileSet() operation for loading uncached tiles.
-- Remove log statements from server actor. …
The creation of certain log statements (whether or not they were being logged)
was causing significant performance issues.