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  1. Chukwa
  2. CHUKWA-668

Infinite loop in FileTailingAdaptor

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.6.0
    • Fix Version/s: 0.6.0
    • Component/s: Data Collection
    • Labels:
      None
    • Tags:
      rotating and tailing file

      Description

      In LWFTAdaptor.java, lastSlurpTime is never updated, triggering an infinite loop if we use the
      adaptor FileTailingAdaptor and subclass adaptors.

      Loop occurs like this:
      1) lastSlurpTime is never changed and thus always 0.
      2) we append some data to the log file and we do a normal slurp
      3) after this slurp, we have: len == fileReadOffset && fixedNameLastModified > lastSlurpTime
      thus we think log file has rotated when it hasn't: fileReadOffset is reset to 0
      4) we get: len > fileReadOffset and so we do a slurp of len bytes.
      5) we are in the same situation as 3) -> infinite loop: the agent never stops sending chunks
      to the collector although log files does not change.

      It seems like this bug comes from CHUKWA-646. The first patch tailfile.patch seemed to do it
      right but in the second patch, the line "lastSlurpTime = System.currentTimeMillis();" just
      disapeared from LWFTAdaptor.java.

        Attachments

        1. chukwa-668-2.patch
          4 kB
          Sourygna Luangsay
        2. chukwa-668.patch
          2 kB
          Sourygna Luangsay

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              • Assignee:
                sourygna Sourygna Luangsay
                Reporter:
                sourygna Sourygna Luangsay
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                Dates

                • Created:
                  Updated:
                  Resolved: