Application log excerpts from two runs of Mapper::Agent, first with 200 records,
then with 800 records. 

200-record mapping run:
[2016-03-10 16:43:26 -0500] [22011] [Krikri] Activity Krikri::Mapper::Agent-23 is running
[2016-03-10 16:48:56 -0500] [22011] [Krikri] START MEM: 253.38916015625 Mb
[2016-03-10 16:48:56 -0500] [22011] [Krikri] FINISH MEM: 439.8388671875 Mb
[2016-03-10 16:48:56 -0500] [22011] [Krikri] Mapper.map took 329.8232810497284 s
[2016-03-10 16:48:56 -0500] [22011] [Krikri] Activity#entity_uris took 3.402691125869751 s
[2016-03-10 16:48:56 -0500] [22011] [Krikri] #run: 0.01171875 Mb inside
[2016-03-10 16:48:56 -0500] [22011] [Krikri] #run: 186.44970703125 Mb outside
[2016-03-10 16:48:56 -0500] [22011] [Krikri] Mapping#process_record: 102.13623046875 Mb
[2016-03-10 16:48:56 -0500] [22011] [Krikri] OriginalRecordEntityBehavior#entities: 2.11328125 Mb
[2016-03-10 16:48:56 -0500] [22011] [Krikri] Activity#entity_uris each_solution: 0.83203125 Mb


800-record mapping run:
[2016-03-11 10:19:26 -0500] [7297] [Krikri] Activity Krikri::Mapper::Agent-23 is running
[2016-03-11 10:58:56 -0500] [7297] [Krikri] START MEM: 245.865234375 Mb
[2016-03-11 10:58:56 -0500] [7297] [Krikri] FINISH MEM: 481.931640625 Mb
[2016-03-11 10:58:56 -0500] [7297] [Krikri] Mapper.map took 2370.538697242737 s
[2016-03-11 10:58:56 -0500] [7297] [Krikri] Activity#entity_uris took 11.078043699264526 s
[2016-03-11 10:58:56 -0500] [7297] [Krikri] #run: 0.32421875 Mb inside
[2016-03-11 10:58:56 -0500] [7297] [Krikri] #run: 236.06640625 Mb outside
[2016-03-11 10:58:56 -0500] [7297] [Krikri] Mapping#process_record: 108.37353515625 Mb
[2016-03-11 10:58:56 -0500] [7297] [Krikri] OriginalRecordEntityBehavior#entities: 2.11328125 Mb
[2016-03-11 10:58:56 -0500] [7297] [Krikri] Activity#entity_uris each_solution: 0.85546875 Mb

200 records 3/10 16:43:26 - 16:48:56 :: Mapper.map took 330 s
    - 05:40 total time, 05:30 of which was Mapper.map
800 records 3/11 10:19:26 - 10:58:56 :: Mapper.map took 2371 s
    - 39:40 total time, 39:31 of which was Mapper.map
... 4x the records, 7x the time.  But not nearly as rapid an increase in memory,
    at least not with this few records.
... Both jobs began and ended on the same second of the minute. This is not true
    of all jobs.