mr4c

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HN mentions by month2 dated mentions

Observed mentions: 2015-02-19 01:01:48 UTC to 2016-10-17 11:09:14 UTC.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

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Period	Start (UTC)	End (exclusive, UTC)	Mentions	Comments
Feb 2015	2015-02-01 00:00:00 UTC	2015-03-01 00:00:00 UTC	1	1
Mar 2015	2015-03-01 00:00:00 UTC	2015-04-01 00:00:00 UTC	0	0
Apr 2015	2015-04-01 00:00:00 UTC	2015-05-01 00:00:00 UTC	0	0
May 2015	2015-05-01 00:00:00 UTC	2015-06-01 00:00:00 UTC	0	0
Jun 2015	2015-06-01 00:00:00 UTC	2015-07-01 00:00:00 UTC	0	0
Jul 2015	2015-07-01 00:00:00 UTC	2015-08-01 00:00:00 UTC	0	0
Aug 2015	2015-08-01 00:00:00 UTC	2015-09-01 00:00:00 UTC	0	0
Sep 2015	2015-09-01 00:00:00 UTC	2015-10-01 00:00:00 UTC	0	0
Oct 2015	2015-10-01 00:00:00 UTC	2015-11-01 00:00:00 UTC	0	0
Nov 2015	2015-11-01 00:00:00 UTC	2015-12-01 00:00:00 UTC	0	0
Dec 2015	2015-12-01 00:00:00 UTC	2016-01-01 00:00:00 UTC	0	0
Jan 2016	2016-01-01 00:00:00 UTC	2016-02-01 00:00:00 UTC	0	0
Feb 2016	2016-02-01 00:00:00 UTC	2016-03-01 00:00:00 UTC	0	0
Mar 2016	2016-03-01 00:00:00 UTC	2016-04-01 00:00:00 UTC	0	0
Apr 2016	2016-04-01 00:00:00 UTC	2016-05-01 00:00:00 UTC	0	0
May 2016	2016-05-01 00:00:00 UTC	2016-06-01 00:00:00 UTC	0	0
Jun 2016	2016-06-01 00:00:00 UTC	2016-07-01 00:00:00 UTC	0	0
Jul 2016	2016-07-01 00:00:00 UTC	2016-08-01 00:00:00 UTC	0	0
Aug 2016	2016-08-01 00:00:00 UTC	2016-09-01 00:00:00 UTC	0	0
Sep 2016	2016-09-01 00:00:00 UTC	2016-10-01 00:00:00 UTC	0	0
Oct 2016	2016-10-01 00:00:00 UTC	2016-11-01 00:00:00 UTC	1	1

2 sources

Hmmm, this is definitely not some sort of vanilla C interface for Hadoop. MR4C is rather a ~40ksloc C++/Java library capable of performing somewhat high-level operations on datasets. It's closer to a MapReduce app or a tool like Pig than a simple C/C++ wrapper. In particular, MR4C has its own data model: * https://github.com/google/mr4c/tree/master/tutorial/UserGuid... ... and nontrivial logging, traceback debugging, tempfile handling.. stuff for writing a library in MR4C * https://github.com/google/mr4c/blob/master/native/src/cpp/im... * https://github.com/google/mr4c/blob/master/native/src/cpp/im... * https://github.com/google/mr4c/blob/master/native/src/cpp/im... ... and a 3600 line C++ package for extracting crops from satellite images based upon geospatial coordinates (that is likely more relevant to Skybox than Hadoop users) * ht

Read the rest

tps://github.com/google/mr4c/tree/master/geospatial ... and singletons all over the place! (Kenton Varda would not be happy) * https://github.com/google/mr4c/blob/master/native/src/cpp/ap... Props to the Skybox devs for getting this out. All of this code almost certainly got thrown away as part of Skybox's transition onto the Google stack. Have not yet found any benchmarks or illustrations of I/O savings.