Solr statsCache implementation LRUStatsCache throws NullPointerException - solr

Question

I have massive problems with the Solr statsCache feature. Here is the feature request in JIRA. I'm using one collection with two shards and a replication factor of two.
In the solrconfig.xml I add the following statsCache implementation:
<statsCache class="org.apache.solr.search.stats.LRUStatsCache"/>
I must use the statsCache feature, because in the base shard are more documents as in the edit shard. But the score must be global.
When I query something which starts a score calculation I get sometimes and not determinist the following exception:
java.lang.NullPointerException
at org.apache.solr.search.stats.LRUStatsCache.getPerShardTermStats(LRUStatsCache.java:122)
at org.apache.solr.search.stats.ExactStatsCache.sendGlobalStats(ExactStatsCache.java:237)
at org.apache.solr.handler.component.QueryComponent.createMainQuery(QueryComponent.java:922)
at org.apache.solr.handler.component.QueryComponent.regularDistributedProcess(QueryComponent.java:713)
at org.apache.solr.handler.component.QueryComponent.distributedProcess(QueryComponent.java:666)
at org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:305)
at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:143)
at org.apache.solr.core.SolrCore.execute(SolrCore.java:2064)
at org.apache.solr.servlet.HttpSolrCall.execute(HttpSolrCall.java:654)
at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:450)
at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:227)
at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:196)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
at org.eclipse.jetty.server.Server.handle(Server.java:497)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
at java.lang.Thread.run(Thread.java:722)
The request q=*:* works fine everytime. But q=SomeTerm results sometimes in the NullPointerException.
I tried all statsCache implementation.
It was not possible for me to detect the problem. Can somebody help me with this?
Please leave a comment if you need more information.

Answer 1

I shared this question on Twitter with #ApacheSolr. It's a bug which should be fixed in Solr 5.3 which should be released in the 1st week of August.
Here is the converstation:
Solr statsCache implementation LRUStatsCache throws
NullPointerException http://t.co/dLT7aygoye /cc #ApacheSolr
(Link)
#tim_krueger we're aware of the bug. Should be fixed in the next
release 5.3. See https://t.co/kt7QredwKr
(Link)
#ApacheSolr Thanks for the answer. Is there a known release date for
5.3?
(Link)
#tim_krueger can't say for sure but typically releases happen every
30-40 days so we can expect one around 1st week of August.
(Link)