Uploaded image for project: 'Lucene - Core'
  1. Lucene - Core
  2. LUCENE-1282

Sun hotspot compiler bug in 1.6.0_04/05 affects Lucene

Details

    • Bug
    • Status: Closed
    • Minor
    • Resolution: Fixed
    • 2.3, 2.3.1
    • 2.4
    • core/index
    • None
    • New

    Description

      This is not a Lucene bug. It's an as-yet not fully characterized Sun
      JRE bug, as best I can tell. I'm opening this to gather all things we
      know, and to work around it in Lucene if possible, and maybe open an
      issue with Sun if we can reduce it to a compact test case.

      It's hit at least 3 users:

      http://mail-archives.apache.org/mod_mbox/lucene-java-user/200803.mbox/%3c8c4e68610803180438x39737565q9f97b4802ed774a5@mail.gmail.com%3e
      http://mail-archives.apache.org/mod_mbox/lucene-solr-user/200804.mbox/%3c4807654E.7050900@virginia.edu%3e
      http://mail-archives.apache.org/mod_mbox/lucene-java-user/200805.mbox/%3c733777220805060156t7fdb8fectf0bc984fbfe48a22@mail.gmail.com%3e

      It's specific to at least JRE 1.6.0_04 and 1.6.0_05, that affects
      Lucene. Whereas 1.6.0_03 works OK and it's unknown whether 1.6.0_06
      shows it.

      The bug affects bulk merging of stored fields. When it strikes, the
      segment produced by a merge is corrupt because its fdx file (stored
      fields index file) is missing one document. After iterating many
      times with the first user that hit this, adding diagnostics &
      assertions, its seems that a call to fieldsWriter.addDocument some
      either fails to run entirely, or, fails to invoke its call to
      indexStream.writeLong. It's as if when hotspot compiles a method,
      there's some sort of race condition in cutting over to the compiled
      code whereby a single method call fails to be invoked (speculation).

      Unfortunately, this corruption is silent when it occurs and only later
      detected when a merge tries to merge the bad segment, or an
      IndexReader tries to open it. Here's a typical merge exception:

      Exception in thread "Thread-10" 
      org.apache.lucene.index.MergePolicy$MergeException: 
      org.apache.lucene.index.CorruptIndexException:
          doc counts differ for segment _3gh: fieldsReader shows 15999 but segmentInfo shows 16000
              at org.apache.lucene.index.ConcurrentMergeScheduler$MergeThread.run(ConcurrentMergeScheduler.java:271)
      Caused by: org.apache.lucene.index.CorruptIndexException: doc counts differ for segment _3gh: fieldsReader shows 15999 but segmentInfo shows 16000
              at org.apache.lucene.index.SegmentReader.initialize(SegmentReader.java:313)
              at org.apache.lucene.index.SegmentReader.get(SegmentReader.java:262)
              at org.apache.lucene.index.SegmentReader.get(SegmentReader.java:221)
              at org.apache.lucene.index.IndexWriter.mergeMiddle(IndexWriter.java:3099)
              at org.apache.lucene.index.IndexWriter.merge(IndexWriter.java:2834)
              at org.apache.lucene.index.ConcurrentMergeScheduler$MergeThread.run(ConcurrentMergeScheduler.java:240)
      

      and here's a typical exception hit when opening a searcher:

      org.apache.lucene.index.CorruptIndexException: doc counts differ for segment _kk: fieldsReader shows 72670 but segmentInfo shows 72671
              at org.apache.lucene.index.SegmentReader.initialize(SegmentReader.java:313)
              at org.apache.lucene.index.SegmentReader.get(SegmentReader.java:262)
              at org.apache.lucene.index.SegmentReader.get(SegmentReader.java:230)
              at org.apache.lucene.index.DirectoryIndexReader$1.doBody(DirectoryIndexReader.java:73)
              at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:636)
              at org.apache.lucene.index.DirectoryIndexReader.open(DirectoryIndexReader.java:63)
              at org.apache.lucene.index.IndexReader.open(IndexReader.java:209)
              at org.apache.lucene.index.IndexReader.open(IndexReader.java:173)
              at org.apache.lucene.search.IndexSearcher.<init>(IndexSearcher.java:48)
      

      Sometimes, adding -Xbatch (forces up front compilation) or -Xint
      (disables compilation) to the java command line works around the
      issue.

      Here are some of the OS's we've seen the failure on:

      SuSE 10.0
      Linux phoebe 2.6.13-15-smp #1 SMP Tue Sep 13 14:56:15 UTC 2005 x86_64 
      x86_64 x86_64 GNU/Linux 
      
      SuSE 8.2
      Linux phobos 2.4.20-64GB-SMP #1 SMP Mon Mar 17 17:56:03 UTC 2003 i686 
      unknown unknown GNU/Linux 
      
      Red Hat Enterprise Linux Server release 5.1 (Tikanga)
      Linux lab8.betech.virginia.edu 2.6.18-53.1.14.el5 #1 SMP Tue Feb 19 
      07:18:21 EST 2008 i686 i686 i386 GNU/Linux
      

      I've already added assertions to Lucene to detect when this bug
      strikes, but since assertions are not usually enabled, I plan to add a
      real check to catch when this bug strikes before we commit the merge
      to the index. This way we can detect & quarantine the failure and
      prevent corruption from entering the index.

      Attachments

        1. corrupt_merge_out15.txt
          49 kB
          Stu Hood
        2. crashtest
          1 kB
          andreaskohn
        3. crashtest.log
          2 kB
          andreaskohn
        4. hs_err_pid27359.log
          13 kB
          Michael McCandless

        Activity

          People

            mikemccand Michael McCandless
            mikemccand Michael McCandless
            Votes:
            5 Vote for this issue
            Watchers:
            8 Start watching this issue

            Dates

              Created:
              Updated:
              Resolved: