[SOLR-13240] UTILIZENODE action results in an exception

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 7.6, 7.7, 7.7.1, 7.7.2, 8.0, 8.1, 8.1.1, 8.2
• Fix Version/s: 8.3, 9.0
• Component/s: AutoScaling
• Assignee: Christine Poerschke
• Reporter: Hendrik Haddorp
• Created: 10/Feb/19 11:39
• Updated: 12/May/22 00:25
• Resolved: 06/Sep/19 12:13

Description

When I invoke the UTILIZENODE action the REST call fails like this after it moved a few replicas:
{
"responseHeader":

{ "status":500, "QTime":40220}

,
"Operation utilizenode caused exception:":"java.lang.IllegalArgumentException:java.lang.IllegalArgumentException: Comparison method violates its general contract!",
"exception":

{ "msg":"Comparison method violates its general contract!", "rspCode":-1}

,
"error":{
"metadata":[
"error-class","org.apache.solr.common.SolrException",
"root-error-class","org.apache.solr.common.SolrException"],
"msg":"Comparison method violates its general contract!",
"trace":"org.apache.solr.common.SolrException: Comparison method violates its general contract!\n\tat org.apache.solr.client.solrj.SolrResponse.getException(SolrResponse.java:53)\n\tat org.apache.solr.handler.admin.CollectionsHandler.invokeAction(CollectionsHandler.java:274)\n\tat org.apache.solr.handler.admin.CollectionsHandler.handleRequestBody(CollectionsHandler.java:246)\n\tat org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:199)\n\tat org.apache.solr.servlet.HttpSolrCall.handleAdmin(HttpSolrCall.java:734)\n\tat org.apache.solr.servlet.HttpSolrCall.handleAdminRequest(HttpSolrCall.java:715)\n\tat org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:496)\n\tat org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:377)\n\tat org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:323)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1634)\n\tat org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146)\n\tat org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)\n\tat org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257)\n\tat org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)\n\tat org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1317)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)\n\tat org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473)\n\tat org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)\n\tat org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1219)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)\n\tat org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:219)\n\tat org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:126)\n\tat org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)\n\tat org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:335)\n\tat org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)\n\tat org.eclipse.jetty.server.Server.handle(Server.java:531)\n\tat org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:352)\n\tat org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260)\n\tat org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:281)\n\tat org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:102)\n\tat org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)\n\tat org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)\n\tat org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)\n\tat org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)\n\tat org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)\n\tat org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)\n\tat org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:762)\n\tat org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:680)\n\tat java.lang.Thread.run(Thread.java:748)\n",
"code":500}}

The logs show this additional exception:
2019-02-10 00:09:00.539 ERROR (OverseerThreadFactory-1268-thread-38-processing-n:agent2:9151_solr) [ ] o.a.s.c.a.c.OverseerCollectionMessageHandler Operation utilizenode failed:java.lang.IllegalArgumentException: Comparison method violates its general contract!
at java.util.TimSort.mergeLo(TimSort.java:777)
at java.util.TimSort.mergeAt(TimSort.java:514)
at java.util.TimSort.mergeCollapse(TimSort.java:439)
at java.util.TimSort.sort(TimSort.java:245)
at java.util.Arrays.sort(Arrays.java:1512)
at java.util.ArrayList.sort(ArrayList.java:1462)
at org.apache.solr.client.solrj.cloud.autoscaling.MoveReplicaSuggester.tryEachNode(MoveReplicaSuggester.java:50)
at org.apache.solr.client.solrj.cloud.autoscaling.MoveReplicaSuggester.init(MoveReplicaSuggester.java:38)
at org.apache.solr.client.solrj.cloud.autoscaling.Suggester.getSuggestion(Suggester.java:187)
at org.apache.solr.cloud.api.collections.UtilizeNodeCmd.call(UtilizeNodeCmd.java:100)
at org.apache.solr.cloud.api.collections.OverseerCollectionMessageHandler.processMessage(OverseerCollectionMessageHandler.java:259)
at org.apache.solr.cloud.OverseerTaskProcessor$Runner.run(OverseerTaskProcessor.java:478)
at org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor.lambda$execute$0(ExecutorUtil.java:209)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

I suspect this to be caused by this comparator: https://github.com/apache/lucene-solr/blob/master/solr/solrj/src/java/org/apache/solr/client/solrj/cloud/autoscaling/MoveReplicaSuggester.java#L98
In case it is possible that both compared replicas are leaders the result would not be correct.

see also the mail thread about this:
https://www.mail-archive.com/search?l=[e-mail]&q=subject:%22Re%5C%3A+CloudSolrClient+getDocCollection%22&o=newest&f=1