# NullPointerException in scroll **URL:** \ **Category:** Elasticsearch\ **Created:** [August 29, 2017, 2:55pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717 "2017-08-29T14:55:13Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Dan\_Markhasin](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dan_markhasin/32/14187_2.png) [@Dan\_Markhasin](https://discuss.elastic.co/u/Dan_Markhasin)\ **Post date:** [August 29, 2017, 2:55pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/1 "2017-08-29T14:55:13Z")
I've noticed this error today in the logs of our 5.4 cluster when running a scroll query - one that ran with no issues before and is running with no issues after this exception, which I was not able to reproduce. Has anyone seen this before? Any idea what could be causing it? > [2017-08-29T11:17:29,137][DEBUG][o.e.a.s.TransportSearchScrollAction] [data1-iil-003] [569527] Failed to execute query phase > org.elasticsearch.transport.RemoteTransportException: [data1-iil-003][x.x.x.x:9300][indices:data/read/search[phase/query+fetch/scroll]] > Caused by: java.lang.NullPointerException > at org.elasticsearch.search.DefaultSearchContext.isCancelled(DefaultSearchContext.java:810) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:138) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:294) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:391) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchTransportService$10.messageReceived(SearchTransportService.java:374) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchTransportService$10.messageReceived(SearchTransportService.java:371) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.RequestHandlerRegistry.processMessageReceived(RequestHandlerRegistry.java:69) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$7.doRun(TransportService.java:627) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:638) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37) [elasticsearch-5.4.0.jar:5.4.0] > at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0\_92] > at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0\_92] > at java.lang.Thread.run(Thread.java:745) [?:1.8.0\_92] > [2017-08-29T11:17:29,179][WARN][r.suppressed] path: /\_search/scroll, params: {scroll=300000ms} > org.elasticsearch.action.search.SearchPhaseExecutionException: all shards failed > at org.elasticsearch.action.search.SearchScrollQueryAndFetchAsyncAction.onPhaseFailure(SearchScrollQueryAndFetchAsyncAction.java:159) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchScrollQueryAndFetchAsyncAction.access$300(SearchScrollQueryAndFetchAsyncAction.java:42) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchScrollQueryAndFetchAsyncAction$1.onFailure(SearchScrollQueryAndFetchAsyncAction.java:146) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.ActionListenerResponseHandler.handleException(ActionListenerResponseHandler.java:51) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$ContextRestoreResponseHandler.handleException(TransportService.java:1041) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$DirectResponseChannel.processException(TransportService.java:1145) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$DirectResponseChannel.sendResponse(TransportService.java:1123) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$7.onFailure(TransportService.java:638) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.onFailure(ThreadContext.java:623) [elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:39) [elasticsearch-5.4.0.jar:5.4.0] > at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0\_92] > at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0\_92] > at java.lang.Thread.run(Thread.java:745) [?:1.8.0\_92] > Caused by: org.elasticsearch.transport.RemoteTransportException: [data1-iil-003][x.x.x.x:9300][indices:data/read/search[phase/query+fetch/scroll]] > Caused by: java.lang.NullPointerException > at org.elasticsearch.search.DefaultSearchContext.isCancelled(DefaultSearchContext.java:810) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:138) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:294) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:391) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchTransportService$10.messageReceived(SearchTransportService.java:374) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.action.search.SearchTransportService$10.messageReceived(SearchTransportService.java:371) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.RequestHandlerRegistry.processMessageReceived(RequestHandlerRegistry.java:69) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.transport.TransportService$7.doRun(TransportService.java:627) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:638) ~[elasticsearch-5.4.0.jar:5.4.0] > at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37) ~[elasticsearch-5.4.0.jar:5.4.0] ---
**Author:** ![thiago](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/thiago/32/32096_2.png) [@thiago](https://discuss.elastic.co/u/thiago)\ **Post date:** [September 6, 2017, 12:05am UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/2 "2017-09-06T00:05:37Z")
This is a DEBUG level message and you should not be worried about it. Actually, enabling DEBUG in production is not recommended and you should only do it when looking for specific issues. Cheers ---
**Author:** ![Dan\_Markhasin](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dan_markhasin/32/14187_2.png) [@Dan\_Markhasin](https://discuss.elastic.co/u/Dan_Markhasin)\ **Post date:** [September 6, 2017, 4:43am UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/3 "2017-09-06T04:43:12Z")
We don't have DEBUG logging level enabled, yet this error appeared anyway in the logs. Also I would not be worried about it if it didn't cause client queries to fail with a NPE error, but it does. ---
**Author:** ![thiago](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/thiago/32/32096_2.png) [@thiago](https://discuss.elastic.co/u/thiago)\ **Post date:** [September 6, 2017, 5:02am UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/4 "2017-09-06T05:02:19Z")
Well, the error _is_ a DEBUG level log message. There is _no_ way for it to show up in the logs if DEBUG level is not enabled. But if you have a client that is getting the error then it explains why it is being logged as DEBUG in the server. That NPE is being caused by the fact that the reference to SearchTask is null. Maybe @Igor_Motov could shed a light here? ---
**Author:** ![Igor\_Motov](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/igor_motov/32/45193_2.png) [@Igor\_Motov](https://discuss.elastic.co/u/Igor_Motov)\ **Post date:** [September 6, 2017, 4:26pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/5 "2017-09-06T16:26:25Z")
I saw something like this recently in [https://github.com/elastic/elasticsearch/issues/25820](https://github.com/elastic/elasticsearch/issues/25820) We are still trying to figure out what's causing it. I suspect that it might have something to do with scroll timeouts, but I am not totally sure about the concrete mechanism. @Dan_Markhasin do you see any other messages in the log file on other nodes around the same time? Which JVM and on which platform are you using to run elasticsearch? ---
**Author:** ![Dan\_Markhasin](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dan_markhasin/32/14187_2.png) [@Dan\_Markhasin](https://discuss.elastic.co/u/Dan_Markhasin)\ **Post date:** [September 6, 2017, 5:42pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/6 "2017-09-06T17:42:20Z")
We are running on Java 1.8.0.92 on SLES11SP4. I do not know if this is related to scroll timeouts - from our logs I can see that the query that triggered this condition failed after ~2 seconds. Also unlike the GitHub issue, there were no other errors in the logs on any of the machines except the one I pasted above - in fact these were the only entries in the ES log on that machine for the entire day when that happened. I also have not been able to reproduce this - I have seen this happen twice so far, completely at random, and it has not reoccurred since I opened this thread. ---
**Author:** ![Igor\_Motov](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/igor_motov/32/45193_2.png) [@Igor\_Motov](https://discuss.elastic.co/u/Igor_Motov)\ **Post date:** [September 7, 2017, 1:46pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/7 "2017-09-07T13:46:27Z")
I am still trying to figure out how this situation can occur, but I have a few more questions about your setup. - Do you know if this scroll query was executed against a singe shard or multiple shards? - Were there any pre-5.4.0 nodes in the cluster when this error occurred? Are you using any plugins in this cluster? - Do you know if it failed on the last page of the results or somewhere in the middle? > I do not know if this is related to scroll timeouts - from our logs I can see that the query that triggered this condition failed after ~2 seconds. Can you clarify what you meant by this? According to the stack trace, this was a scroll query, which typically consists of multiple requests. Did it take 2 seconds between the first request that initiated the scroll and this last request that failed or it took 2 seconds just for the last request to fail? ---
**Author:** ![Dan\_Markhasin](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dan_markhasin/32/14187_2.png) [@Dan\_Markhasin](https://discuss.elastic.co/u/Dan_Markhasin)\ **Post date:** [September 7, 2017, 3:15pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/8 "2017-09-07T15:15:23Z")
1. It was executed against a specific shard 2. No, the cluster is homogenous (5.4.1) 3. Unfortunately I don't know When I said it failed after 2 seconds I meant that 2 seconds had passed since the first request that initiated the scroll to the request that failed. ---
**Author:** ![Igor\_Motov](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/igor_motov/32/45193_2.png) [@Igor\_Motov](https://discuss.elastic.co/u/Igor_Motov)\ **Post date:** [September 7, 2017, 3:44pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/9 "2017-09-07T15:44:49Z")
> [@Dan\_Markhasin](#): > > No, the cluster is homogenous (5.4.1) Hmm, according to the stacktrace, the node that failed was 5.4.0, not 5.4.1. ---
**Author:** ![Dan\_Markhasin](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dan_markhasin/32/14187_2.png) [@Dan\_Markhasin](https://discuss.elastic.co/u/Dan_Markhasin)\ **Post date:** [September 7, 2017, 3:57pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/10 "2017-09-07T15:57:52Z")
Oh, sorry, you're correct. It is indeed 5.4.0. I mixed up with a different cluster that was 5.4.1 at the time. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [October 5, 2017, 3:57pm UTC](https://discuss.elastic.co/t/nullpointerexception-in-scroll/98717/11 "2017-10-05T15:57:56Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.