title: Read Timed out in solrcloud
body: <p>We are using solrcloud 6.3. We have a collection say "MyCore". It is divided in two shards and two replicas. Each shard is located on single server.</p>
  
  <blockquote>
    <p><strong>Specifications</strong>: Index size 4 GB, heap size 2 GB, Total Ram on machine: 40 GB, Number of CPUs: 32.</p>
  </blockquote>
  
  <p>Our indexing job runs once in a minute and We using using Zookeeper to add documents to solr. Here is the commit configuration from solrconfig.xml</p>
  
  <pre><code>&lt;updateHandler class="solr.DirectUpdateHandler2"&gt;
  &lt;maxPendingDeletes&gt;100000&lt;/maxPendingDeletes&gt;
  &lt;updateLog&gt;
       &lt;int name="numRecordsToKeep"&gt;200&lt;/int&gt;
       &lt;int name="maxNumLogsToKeep"&gt;5&lt;/int&gt;
  &lt;/updateLog&gt;
  &lt;autoCommit&gt;
      &lt;maxDocs&gt;500&lt;/maxDocs&gt;
      &lt;maxTime&gt;120000&lt;/maxTime&gt;
      &lt;openSearcher&gt;false&lt;/openSearcher&gt;
   &lt;/autoCommit&gt;
   &lt;autoSoftCommit&gt;
       &lt;maxDocs&gt;300&lt;/maxDocs&gt;
       &lt;maxTime&gt;60000&lt;/maxTime&gt;
    &lt;/autoSoftCommit&gt;
  </code></pre>
  
  <p></p>
  
  <p>We are seeing read timed out exceptions in solr logs and at that time solr becomes unresponsive for some time like 30 seconds and after 30 seconds it comes up automatically without taking a restart. Just want to mention here that we have analysed GC logs and nothing unsual is found. GC activity is healthy.
  Attaching logs.</p>
  
  <blockquote>
    <p></p>
  </blockquote>
  
  <pre><code>2017-11-06 07:05:00.121 ERROR (updateExecutor-2-thread-624-processing-n:192.168.0.1:8983_solr x:MyCore_shard2_replica1 s:shard2 c:MyCore r:core_node3) [c:MyCore s:shard2 r:core_node3 x:MyCore_shard2_replica1] o.a.s.u.SolrCmdDistributor org.apache.solr.client.solrj.SolrServerException: Timeout occured while waiting response from server at: http://192.168.0.4:8983/solr/MyCore_shard1_replica3
      at org.apache.solr.client.solrj.impl.HttpSolrClient.executeMethod(HttpSolrClient.java:604)
      at org.apache.solr.client.solrj.impl.HttpSolrClient.request(HttpSolrClient.java:262)
      at org.apache.solr.client.solrj.impl.HttpSolrClient.request(HttpSolrClient.java:251)
      at org.apache.solr.client.solrj.impl.ConcurrentUpdateSolrClient.request(ConcurrentUpdateSolrClient.java:420)
      at org.apache.solr.client.solrj.SolrClient.request(SolrClient.java:1219)
      at org.apache.solr.update.SolrCmdDistributor.doRequest(SolrCmdDistributor.java:293)
      at org.apache.solr.update.SolrCmdDistributor.lambda$submit$0(SolrCmdDistributor.java:282)
      at org.apache.solr.update.SolrCmdDistributor$$Lambda$119/389184320.call(Unknown Source)
      at java.util.concurrent.FutureTask.run(FutureTask.java:266)
      at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
      at java.util.concurrent.FutureTask.run(FutureTask.java:266)
      at org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor.lambda$execute$0(ExecutorUtil.java:229)
      at org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor$$Lambda$8/534303375.run(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at java.lang.Thread.run(Thread.java:744)
  Caused by: java.net.SocketTimeoutException: Read timed out
      at java.net.SocketInputStream.socketRead0(Native Method)
      at java.net.SocketInputStream.read(SocketInputStream.java:150)
      at java.net.SocketInputStream.read(SocketInputStream.java:121)
      at org.apache.http.impl.io.AbstractSessionInputBuffer.fillBuffer(AbstractSessionInputBuffer.java:160)
      at org.apache.http.impl.io.SocketInputBuffer.fillBuffer(SocketInputBuffer.java:84)
      at org.apache.http.impl.io.AbstractSessionInputBuffer.readLine(AbstractSessionInputBuffer.java:273)
      at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:140)
      at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:57)
      at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:261)
      at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientConnection.java:283)
      at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnection.java:251)
      at org.apache.http.impl.conn.ManagedClientConnectionImpl.receiveResponseHeader(ManagedClientConnectionImpl.java:197)
      at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:272)
      at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:124)
      at org.apache.http.impl.client.DefaultRequestDirector.tryExecute(DefaultRequestDirector.java:685)
      at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:487)
      at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:882)
      at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
      at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:55)
      at org.apache.solr.client.solrj.impl.HttpSolrClient.executeMethod(HttpSolrClient.java:498)
      ... 15 more
  </code></pre>