title: Solr - LockObtainFailedException on multiple simultaneous writes
body: <p>My application does very frequent solr writes from multiple clients via REST. I'm using the autocommit feature by using the "commitWithin" attribute. LockObtainFailedException start appearing after couple of days of use. I'm having a hard time figuring out what the problem might be. Any help is appreciated. I'm using Solr 3.1 with tomcat 6</p>
  
  <p>here is the error dump from solr</p>
  
  <hr>
  
  <pre><code>HTTP Status 500 - Lock obtain timed out:      NativeFSLock@/var/lib/solr/data/index/write.lock
  
  org.apache.lucene.store.LockObtainFailedException: Lock obtain timed out: NativeFSLock@/var/lib/solr/data/index/write.lock
  at org.apache.lucene.store.Lock.obtain(Lock.java:84)
  at org.apache.lucene.index.IndexWriter.&amp;lt;init&amp;gt;(IndexWriter.java:1097)
  at org.apache.solr.update.SolrIndexWriter.&amp;lt;init&amp;gt;(SolrIndexWriter.java:83)
  at org.apache.solr.update.UpdateHandler.createMainIndexWriter(UpdateHandler.java:102)
  at org.apache.solr.update.DirectUpdateHandler2.openWriter(DirectUpdateHandler2.java:174)
  at org.apache.solr.update.DirectUpdateHandler2.addDoc(DirectUpdateHandler2.java:222)
  at org.apache.solr.update.processor.RunUpdateProcessor.processAdd(RunUpdateProcessorFactory.java:61)
  at org.apache.solr.handler.XMLLoader.processUpdate(XMLLoader.java:147)
  at org.apache.solr.handler.XMLLoader.load(XMLLoader.java:77)
  at org.apache.solr.handler.ContentStreamHandlerBase.handleRequestBody(ContentStreamHandlerBase.java:55)
  at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:129)
  at org.apache.solr.core.SolrCore.execute(SolrCore.java:1360)
  at org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:356)
  at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:252)
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
  at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
  at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
  at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
  at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
  at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
  at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
  at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
  at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
  at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
  at java.lang.Thread.run(Thread.java:662)
  &lt;/h1&gt;&lt;HR size="1" noshade="noshade"&gt;&lt;p&gt;&lt;b&gt;type&lt;/b&gt; Status report&lt;/p&gt;&lt;p&gt;&lt;b&gt;message&lt;/b&gt; &lt;u&gt;Lock obtain timed out: NativeFSLock@/var/lib/solr/data/index/write.lock
  </code></pre>