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  1. Solr
  2. SOLR-4923

Replica index is one version behind sending the commit to non-leader instance

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Details

    • Bug
    • Status: Closed
    • Critical
    • Resolution: Fixed
    • 4.2
    • 4.4, 6.0
    • replication (java)
    • None
    • Solr 4.2.1
      OS X 10.8.3

    Description

      I was actually trying to debug an issue we experiencing in production where the replica version is ahead from the leader when I noticed this problem.

      For my tests I'm running two Solr instances with distributed updates (SolrCloud). ZK runs embedded within one of the instances.

      The test consists on updating one field in single document. If I send an update to the leader the index is replicated correctly. However, if I run the update against the follower replica only the leader is updated correctly. I can reproduce this using both hard and soft commits. Here is the command I'm running:

      curl "http://localhost:8999/solr/rulePreview/update?commit=true&softCommit=true" -H "Content-Type: text/xml" --data-binary '<add>...</add>

      If I execute a second commit against the follower the leader will have the most recent update and the follower will be update from the first commit.

      For example, my field is named category and initially it contains the value cat_1. If update the value to cat_2 the leader sees the change but the follower doesn't. If a second commit updates the field to cat_3 the leader will return cat_3 but the follower return cat_2.

      Reloading the core in the follower fixes the problem.

      The logs seem to confirm the follower gets the latest index version. However, the version in the logs doesn't matches the on in the Core Admin UI nor Luke. Here are some logs from the leader:

      Jun 12, 2013 10:34:19 PM org.apache.solr.update.processor.LogUpdateProcessor finish
      INFO: [rulePreview_en] webapp=/solr path=/update params=

      {distrib.from=http://192.168.1.106:8998/solr/rulePreview_en/&update.distrib=TOLEADER&wt=javabin&version=2}

      {add=[importedRedirect1 (1437700518392627200)]} 0 11
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.DirectUpdateHandler2 commit
      INFO: start commit{,optimize=false,openSearcher=true,waitSearcher=true,expungeDeletes=false,softCommit=true,prepareCommit=false}
      Jun 12, 2013 10:34:19 PM org.apache.solr.search.SolrIndexSearcher <init>
      INFO: Opening Searcher@47e4e06c main
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.DirectUpdateHandler2 commit
      INFO: end_commit_flush
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.QuerySenderListener newSearcher
      INFO: QuerySenderListener sending requests to Searcher@47e4e06c main{StandardDirectoryReader(segments_3g:467:nrt _2a(4.2.1):C134/1 _3c(4.2.1):C1)}
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.QuerySenderListener newSearcher
      INFO: QuerySenderListener done.
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.SolrCore registerSearcher
      INFO: [rulePreview_en] Registered new searcher Searcher@47e4e06c main{StandardDirectoryReader(segments_3g:467:nrt _2a(4.2.1):C134/1 _3c(4.2.1):C1)}
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.processor.LogUpdateProcessor finish
      INFO: [rulePreview_en] webapp=/solr path=/update params={waitSearcher=true&commit=true&wt=javabin&expungeDeletes=false&commit_end_point=true&version=2&softCommit=true} {commit=} 0 12

      And the logs from the follower:

      Jun 12, 2013 10:34:19 PM org.apache.solr.update.DirectUpdateHandler2 commit
      INFO: start commit{,optimize=false,openSearcher=true,waitSearcher=true,expungeDeletes=false,softCommit=true,prepareCommit=false}
      Jun 12, 2013 10:34:19 PM org.apache.solr.search.SolrIndexSearcher <init>
      INFO: Opening Searcher@1e23cfc main
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.DirectUpdateHandler2 commit
      INFO: end_commit_flush
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.QuerySenderListener newSearcher
      INFO: QuerySenderListener sending requests to Searcher@1e23cfc main{StandardDirectoryReader(segments_3i:463:nrt _2a(4.2.1):C134/1 _3b(4.2.1):C1)}
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.QuerySenderListener newSearcher
      INFO: QuerySenderListener done.
      Jun 12, 2013 10:34:19 PM org.apache.solr.core.SolrCore registerSearcher
      INFO: [rulePreview_en] Registered new searcher Searcher@1e23cfc main{StandardDirectoryReader(segments_3i:463:nrt _2a(4.2.1):C134/1 _3b(4.2.1):C1)}
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.processor.LogUpdateProcessor finish
      INFO: [rulePreview_en] webapp=/solr path=/update params={distrib.from=http://192.168.1.106:8999/solr/rulePreview_en/&update.distrib=FROMLEADER&wt=javabin&version=2} {add=[importedRedirect1 (1437700518392627200)]}

      0 4
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.SolrCmdDistributor distribCommit
      INFO: Distrib commit to:[StdNode: http://192.168.1.106:8999/solr/rulePreview_en/] params:commit_end_point=true&commit=true&softCommit=true&waitSearcher=true&expungeDeletes=false
      Jun 12, 2013 10:34:19 PM org.apache.solr.update.processor.LogUpdateProcessor finish
      INFO: [rulePreview_en] webapp=/solr path=/update params=

      {softCommit=true}

      {add=[importedRedirect1],commit=}

      0 41

      Attachments

        1. SOLR-4923-test-1.patch
          4 kB
          Mark Miller
        2. SOLR-4923.patch
          7 kB
          Mark Miller
        3. SOLR-4923_hoss_test.patch
          8 kB
          Chris M. Hostetter

        Activity

          People

            markrmiller@gmail.com Mark Miller
            rmerizalde Ricardo Merizalde
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            Dates

              Created:
              Updated:
              Resolved: