Uploaded image for project: 'ZooKeeper'
  1. ZooKeeper
  2. ZOOKEEPER-704

GSoC 2010: Read-Only Mode

    XMLWordPrintableJSON

    Details

    • Type: Wish
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: None
    • Labels:

      Description

      Read-only mode
      Possible Mentor
      Henry Robinson (henry at apache dot org)

      Requirements
      Java and TCP/IP networking

      Description
      When a ZooKeeper server loses contact with over half of the other servers in an ensemble ('loses a quorum'), it stops responding to client requests because it cannot guarantee that writes will get processed correctly. For some applications, it would be beneficial if a server still responded to read requests when the quorum is lost, but caused an error condition when a write request was attempted.

      This project would implement a 'read-only' mode for ZooKeeper servers (maybe only for Observers) that allowed read requests to be served as long as the client can contact a server.

      This is a great project for getting really hands-on with the internals of ZooKeeper - you must be comfortable with Java and networking otherwise you'll have a hard time coming up to speed.

        Attachments

          Issue Links

          Dependent

          Bug - A problem which impairs or prevents the functions of the product. REEF-1291 Driver gets FailedEvaluator message even if evaluator shuts down properly

          • Major - Major loss of function.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. SPARK-2876 RDD.partitionBy loads entire partition into memory

          • Major - Major loss of function.
          • Resolved

          Bug - A problem which impairs or prevents the functions of the product. HBASE-2531 32-bit encoding of regionnames waaaaaaayyyyy too susceptible to hash clashes

          • Blocker - Blocks development and/or testing work, production could not run
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. DRILL-4387 Improve execution side when it handles skipAll query

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QPID-6275 reduce default timeout for durable subscription queues

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. DRILL-4530 Improve metadata cache performance for queries with single partition

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. HADOOP-10561 Copy command with preserve option should handle Xattrs

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. HDFS-3259 NameNode#initializeSharedEdits should populate shared edits dir with edit log segments

          • Major - Major loss of function.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. ZOOKEEPER-769 Leader can treat observers as quorum members

          • Major - Major loss of function.
          • Closed

            Activity

              People

              • Assignee:
                dorserg Sergey Doroshenko
                Reporter:
                henryr Henry Robinson
              • Votes:
                0 Vote for this issue
                Watchers:
                6 Start watching this issue

                Dates

                • Created:
                  Updated: