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  1. Hadoop Common
  2. HADOOP-8292

TableMapping does not refresh when topology is updated

    Details

    • Type: Bug
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: 2.0.0-alpha
    • Fix Version/s: None
    • Component/s: None
    • Labels:
      None

      Description

      HADOOP-7030 introduced TableMapping, an implementation of DNSToSwitchMapping which uses a file to map from IPs/hosts to their racks. It's intended to replace ScriptBasedMapping for cases where the latter was just a complicated way of looking up the rack in a file.

      Though there was discussion of it on the JIRA, the TableMapping implementation is not 'refreshable'. i.e., if you want to add a host to your cluster, and that host wasn't in the topology file to begin with, it will never be added.

      TableMapping should refresh, either based on a command that can be executed, or, perhaps, if the file on disk changes.

      I'll also point out that TableMapping extends CachedDNSToSwitchMapping, but, since it does no refreshing, I don't see what the caching gets you: I think the cache ends up being a second copy of the underlying map, always.

        Attachments

        1. HADOOP-8292.patch
          10 kB
          Alejandro Abdelnur
        2. HADOOP-8292.patch
          8 kB
          Alejandro Abdelnur

          Activity

            People

            • Assignee:
              Unassigned
              Reporter:
              philip Philip Zeyliger
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              Dates

              • Created:
                Updated: