Hadoop HDFS
  1. Hadoop HDFS
  2. HDFS-763

DataBlockScanner reporting of bad blocks is slightly misleading

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 0.20.1
    • Fix Version/s: 0.21.0
    • Component/s: datanode
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      The Datanode generates a report of the period block scanning that verifies crcs. It reports something like the following:

      Scans since restart : 192266
      Scan errors since restart : 33
      Transient scan errors : 0

      The statement saying that there were 33 errors is slightly midleading because these are not crc mismatches, rather the block was being deleted when the crc verification was about to happen.

      I propose that DataBlockScanner.totalScanErrors is not updated if the dataset.getFile(block) is null, i.e. the block is now deleted from the datanode.

      1. scanErrors.txt
        0.8 kB
        dhruba borthakur
      2. scanErrors.txt
        0.8 kB
        dhruba borthakur
      3. scanErrors.txt
        2 kB
        dhruba borthakur

        Activity

        Hide
        Hudson added a comment -

        Integrated in Hdfs-Patch-h2.grid.sp2.yahoo.net #81 (See http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h2.grid.sp2.yahoo.net/81/)

        Show
        Hudson added a comment - Integrated in Hdfs-Patch-h2.grid.sp2.yahoo.net #81 (See http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h2.grid.sp2.yahoo.net/81/ )
        Hide
        Hudson added a comment -

        Integrated in Hdfs-Patch-h5.grid.sp2.yahoo.net #118 (See http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/118/)
        . Fix slightly misleading report from DataBlockScanner
        about corrupted scans. (dhruba)

        Show
        Hudson added a comment - Integrated in Hdfs-Patch-h5.grid.sp2.yahoo.net #118 (See http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/118/ ) . Fix slightly misleading report from DataBlockScanner about corrupted scans. (dhruba)
        Hide
        Hudson added a comment -

        Integrated in Hadoop-Hdfs-trunk #145 (See http://hudson.zones.apache.org/hudson/job/Hadoop-Hdfs-trunk/145/)
        . Fix slightly misleading report from DataBlockScanner
        about corrupted scans. (dhruba)

        Show
        Hudson added a comment - Integrated in Hadoop-Hdfs-trunk #145 (See http://hudson.zones.apache.org/hudson/job/Hadoop-Hdfs-trunk/145/ ) . Fix slightly misleading report from DataBlockScanner about corrupted scans. (dhruba)
        Hide
        Hudson added a comment -

        Integrated in Hadoop-Hdfs-trunk-Commit #116 (See http://hudson.zones.apache.org/hudson/job/Hadoop-Hdfs-trunk-Commit/116/)
        . Fix slightly misleading report from DataBlockScanner
        about corrupted scans. (dhruba)

        Show
        Hudson added a comment - Integrated in Hadoop-Hdfs-trunk-Commit #116 (See http://hudson.zones.apache.org/hudson/job/Hadoop-Hdfs-trunk-Commit/116/ ) . Fix slightly misleading report from DataBlockScanner about corrupted scans. (dhruba)
        Hide
        dhruba borthakur added a comment -

        I just committed this.

        Show
        dhruba borthakur added a comment - I just committed this.
        Hide
        Raghu Angadi added a comment -


        I don't think this needs an extra unit test. That stat affected here is only for display purposes and also not related to stats reported to stats servers like simon.

        Show
        Raghu Angadi added a comment - I don't think this needs an extra unit test. That stat affected here is only for display purposes and also not related to stats reported to stats servers like simon.
        Hide
        Raghu Angadi added a comment -

        +1.

        "totalErrors" shown on 'blockScannerReport' now becomes same as number of verification failures, rather than all the errors seen.

        Show
        Raghu Angadi added a comment - +1. "totalErrors" shown on 'blockScannerReport' now becomes same as number of verification failures, rather than all the errors seen.
        Hide
        Hadoop QA added a comment -

        -1 overall. Here are the results of testing the latest attachment
        http://issues.apache.org/jira/secure/attachment/12424830/scanErrors.txt
        against trunk revision 835752.

        +1 @author. The patch does not contain any @author tags.

        -1 tests included. The patch doesn't appear to include any new or modified tests.
        Please justify why no new tests are needed for this patch.
        Also please list what manual steps were performed to verify this patch.

        +1 javadoc. The javadoc tool did not generate any warning messages.

        +1 javac. The applied patch does not increase the total number of javac compiler warnings.

        +1 findbugs. The patch does not introduce any new Findbugs warnings.

        +1 release audit. The applied patch does not increase the total number of release audit warnings.

        -1 core tests. The patch failed core unit tests.

        +1 contrib tests. The patch passed contrib unit tests.

        Test results: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/testReport/
        Findbugs warnings: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html
        Checkstyle results: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/artifact/trunk/build/test/checkstyle-errors.html
        Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/console

        This message is automatically generated.

        Show
        Hadoop QA added a comment - -1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12424830/scanErrors.txt against trunk revision 835752. +1 @author. The patch does not contain any @author tags. -1 tests included. The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch. +1 javadoc. The javadoc tool did not generate any warning messages. +1 javac. The applied patch does not increase the total number of javac compiler warnings. +1 findbugs. The patch does not introduce any new Findbugs warnings. +1 release audit. The applied patch does not increase the total number of release audit warnings. -1 core tests. The patch failed core unit tests. +1 contrib tests. The patch passed contrib unit tests. Test results: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/testReport/ Findbugs warnings: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html Checkstyle results: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/artifact/trunk/build/test/checkstyle-errors.html Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/110/console This message is automatically generated.
        Hide
        dhruba borthakur added a comment -

        Trigger HadoopQA.

        Show
        dhruba borthakur added a comment - Trigger HadoopQA.
        Hide
        Hadoop QA added a comment -

        -1 overall. Here are the results of testing the latest attachment
        http://issues.apache.org/jira/secure/attachment/12424762/scanErrors.txt
        against trunk revision 835752.

        +1 @author. The patch does not contain any @author tags.

        -1 tests included. The patch doesn't appear to include any new or modified tests.
        Please justify why no new tests are needed for this patch.
        Also please list what manual steps were performed to verify this patch.

        -1 patch. The patch command could not apply the patch.

        Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/109/console

        This message is automatically generated.

        Show
        Hadoop QA added a comment - -1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12424762/scanErrors.txt against trunk revision 835752. +1 @author. The patch does not contain any @author tags. -1 tests included. The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch. -1 patch. The patch command could not apply the patch. Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/109/console This message is automatically generated.
        Hide
        dhruba borthakur added a comment -

        Trigger HadoopQA tests

        Show
        dhruba borthakur added a comment - Trigger HadoopQA tests
        Hide
        Hadoop QA added a comment -

        -1 overall. Here are the results of testing the latest attachment
        http://issues.apache.org/jira/secure/attachment/12424762/scanErrors.txt
        against trunk revision 835534.

        +1 @author. The patch does not contain any @author tags.

        -1 tests included. The patch doesn't appear to include any new or modified tests.
        Please justify why no new tests are needed for this patch.
        Also please list what manual steps were performed to verify this patch.

        -1 patch. The patch command could not apply the patch.

        Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/107/console

        This message is automatically generated.

        Show
        Hadoop QA added a comment - -1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12424762/scanErrors.txt against trunk revision 835534. +1 @author. The patch does not contain any @author tags. -1 tests included. The patch doesn't appear to include any new or modified tests. Please justify why no new tests are needed for this patch. Also please list what manual steps were performed to verify this patch. -1 patch. The patch command could not apply the patch. Console output: http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/107/console This message is automatically generated.
        Hide
        dhruba borthakur added a comment -

        Moved the increment of totalScanErrors to follow the check if block was already deleted.

        Show
        dhruba borthakur added a comment - Moved the increment of totalScanErrors to follow the check if block was already deleted.
        Hide
        Raghu Angadi added a comment -

        +1. yes. it should be incremented only for real errors.

        Show
        Raghu Angadi added a comment - +1. yes. it should be incremented only for real errors.

          People

          • Assignee:
            dhruba borthakur
            Reporter:
            dhruba borthakur
          • Votes:
            0 Vote for this issue
            Watchers:
            5 Start watching this issue

            Dates

            • Created:
              Updated:
              Resolved:

              Development