[NEMO-47] Use primitive types for AlternatingLeastSquare

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Done
• Fix Version/s: 0.1
• Labels: examples pull-request-available
• Assignee: John Yang
• Reporter: John Yang
• Created: 09/May/18 07:24
• Updated: 23/Nov/18 05:53
• Resolved: 21/May/18 02:34

Description

Change List<Integer> and List<Double> to int[] and float[].

Using the primitive types gave me around 2X performance improvements for processing a Yahoo! Music dataset. The major benefit comes from creating a significantly fewer number of objects. Using floats instead of doubles also seem to improve overall performance.

Note that Beam does not provide efficient coders for in[] and float[] by default, so we need to add custom coders for those types to avoid using the inefficient Java serializer.

Issue Links

• links to: GitHub Pull Request #19