If you are having an issue when increasing the search request rate you should have a look at maxConnectionsPerHost, I believe maxUpdateConnectionsPerHost is related to indexing. You can modify your solr.xml as follows (I believe it's not clear from the official documentation, I had to go through the code to find out about maxConnectionsPerHost )
<shardHandlerFactory class="HttpShardHandlerFactory" name="shardHandlerFactory"> <int name="connTimeout">15000</int> <int name="socketTimeout">120000</int> <int name="maxConnectionsPerHost">500</int> </shardHandlerFactory> Another thing I'd check is if you have GC pauses, it might affect your performance. -- Sent from: http://lucene.472066.n3.nabble.com/Solr-User-f472068.html