[ACCUMULO-4165] Create a user level API for RFile

• Type: Improvement
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 1.8.0
• Assignee: Keith Turner
• Reporter: Keith Turner
• Created: 14/Mar/16 18:03
• Updated: 14/Jul/16 19:19
• Resolved: 02/Jun/16 21:51

Description

Users can bulk import RFiles. Currently the only way users can create RFiles using Accumulo's public API is via AccumuloFileOutputFormat. There is no way to read RFiles in the public API. Also, the internal APIs for reading and writing RFiles are cumbersome to use.

I am experimenting with a simple RFile API like the following. Below is an example of writing data.

    LocalFileSystem localFs = FileSystem.getLocal(new Configuration());
    RFileWriter writer = RFileFactory.newWriter()
                                       .withFileName("/tmp/test100M.rf")
                                       .withFileSystem(localFs).build();

    writer.startDefaultLocalityGroup();
    for (int r = 0; r < 10000000; r++) {
      for (int cq = 0; cq < 10; cq++) {
        writer.append(genKey(r, cq), genVal(r, cq));
      }
    }

    writer.close();

Below is an example of reading data.

    LocalFileSystem localFs = FileSystem.getLocal(new Configuration());
    Scanner scanner = RFileFactory.newScanner()
                                          .withFileName("/tmp/test100M.rf")
                                          .withFileSystem(localFs)
                                          .withDataCache(250000000)
                                          .withIndexCache(1000000).build();

Issue Links

• links to: GitHub Pull Request #103
• links to: https://github.com/apache/accumulo/pull/103.patch