embedded solr: write lock issue

[Erik Hatcher]

I'm working on a project that embeds Solr, much like the EmbeddedSolr  
example posted here <http://wiki.apache.org/solr/EmbeddedSolr>.

The application generally runs fine, with very rapid handling of  
indexing and search requests, however at heavy load we're  
experiencing "Lock obtain timed out: SimpleFSLock@ ..." errors.  The  
heavy load can be replicated by indexing the same document  
repeatedly, so even a very tiny index experiences this.   The  
application is configured with the following relevant pieces to  
solrconfig.xml:

  <indexDefaults>
   <!-- Values here affect all index writers and act as a default  
unless overridden. -->
    <useCompoundFile>false</useCompoundFile>
    <mergeFactor>10</mergeFactor>
    <maxBufferedDocs>1000</maxBufferedDocs>
    <maxMergeDocs>2147483647</maxMergeDocs>
    <maxFieldLength>10000</maxFieldLength>
    <writeLockTimeout>1000</writeLockTimeout>
    <commitLockTimeout>10000</commitLockTimeout>
  </indexDefaults>

and

    <autoCommit>
      <maxTime>1000</maxTime>
    </autoCommit>

So a commit is never sent, only relying on the autoCommit feature.

What troubleshooting/diagnostic steps do you recommend to dig further  
into this?

At the moment the application is intertwined with domain-specific  
stuff, so I haven't isolated it to a simple sharable situation yet,  
but I'll do that if necessary.

Thanks,
        Erik