[ https://issues.apache.org/jira/browse/HBASE-8505?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13659254#comment-13659254 ]
Lars Hofhansl commented on HBASE-8505: -------------------------------------- +1 The full version of the patch seems fine for 0.94 as well (the reduced version would do too). > References to split daughters should not be deleted separately from parent > META entry > ------------------------------------------------------------------------------------- > > Key: HBASE-8505 > URL: https://issues.apache.org/jira/browse/HBASE-8505 > Project: HBase > Issue Type: Bug > Components: regionserver > Reporter: Enis Soztutar > Assignee: Enis Soztutar > Fix For: 0.98.0, 0.94.8, 0.95.1 > > Attachments: hbase-8505_v1-0.94.patch, hbase-8505_v2-0.94.patch, > hbase-8505_v2-0.94-reduced.patch, hbase-8505_v2.patch, hbase-8505_v2.patch > > > In CatalogJanitor, we clean up the parent regions whose daughters does not > have any more references to their parent regions. In doing so, we do two > Delete's one for removing the split daughter columns, and the other for > removing the row. > The first one seems unnecessary, and causes NPE from concurrent MetaScanner. > Stack trace: > {code} > 2013-05-07 04:49:40,828|machine|INFO|Exception in thread "main" > java.lang.NullPointerException > 2013-05-07 04:49:40,828|machine|INFO|at > org.apache.hadoop.hbase.util.Writables.getWritable(Writables.java:103) > 2013-05-07 04:49:40,828|machine|INFO|at > org.apache.hadoop.hbase.util.Writables.getHRegionInfo(Writables.java:147) > 2013-05-07 04:49:40,829|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner$BlockingMetaScannerVisitor.processRow(MetaScanner.java:406) > 2013-05-07 04:49:40,829|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner$TableMetaScannerVisitor.processRow(MetaScanner.java:487) > 2013-05-07 04:49:40,830|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:224) > 2013-05-07 04:49:40,830|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.access$000(MetaScanner.java:54) > 2013-05-07 04:49:40,830|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner$1.connect(MetaScanner.java:133) > 2013-05-07 04:49:40,831|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner$1.connect(MetaScanner.java:130) > 2013-05-07 04:49:40,831|machine|INFO|at > org.apache.hadoop.hbase.client.HConnectionManager.execute(HConnectionManager.java:384) > 2013-05-07 04:49:40,831|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:130) > 2013-05-07 04:49:40,832|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:105) > 2013-05-07 04:49:40,832|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:83) > 2013-05-07 04:49:40,832|machine|INFO|at > org.apache.hadoop.hbase.client.MetaScanner.allTableRegions(MetaScanner.java:323) > 2013-05-07 04:49:40,833|machine|INFO|at > org.apache.hadoop.hbase.client.HTable.getRegionLocations(HTable.java:485) > 2013-05-07 04:49:40,833|machine|INFO|at > org.apache.hadoop.hbase.client.HTable.getStartEndKeys(HTable.java:438) > {code} > Master is doing the CatalogJanitor concurrently: > {code} > 2013-05-07 04:49:40,636 INFO org.apache.hadoop.hbase.catalog.MetaEditor: > Deleted daughters references, qualifier=splitA and qualifier=splitB, from > parent > IntegrationTestBigLinkedList,\x07\xFB\x98\xB7a\x89\xF5\xE6,1367898577620.4ef1329ff0e8911db998ac8ccd32108d. > 2013-05-07 04:49:40,666 INFO org.apache.hadoop.hbase.catalog.MetaEditor: > Deleted region > IntegrationTestBigLinkedList,\x07\xFB\x98\xB7a\x89\xF5\xE6,1367898577620.4ef1329ff0e8911db998ac8ccd32108d. > from META > 2013-05-07 04:49:40,690 INFO org.apache.hadoop.hbase.catalog.MetaEditor: > Deleted daughters references, qualifier=splitA and qualifier=splitB, from > parent > IntegrationTestBigLinkedList,\x0B\xF8n\xEA\xD3\xAA\xA9\x92,1367898577620.b502376df2623cb0be3f0c1664d799a6. > 2013-05-07 04:49:40,716 INFO org.apache.hadoop.hbase.catalog.MetaEditor: > Deleted region > IntegrationTestBigLinkedList,\x0B\xF8n\xEA\xD3\xAA\xA9\x92,1367898577620.b502376df2623cb0be3f0c1664d799a6. > from META > 2013-05-07 04:49:40,742 INFO org.apache.hadoop.hbase.catalog.MetaEditor: > Deleted daughters references, qualifier=splitA and qualifier=splitB, from > parent > IntegrationTestBigLinkedList,\x17\xF5\x11\xB9\xE3\xDB)\x0C,1367898541729.ec2df58fafb823cec6e793ba35e2241d. > {code} > This is critical for 0.94, but not for 0.95 and trunk due to HBASE-7721. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira