# Index.merge.scheduler exception - java.io.IOException: Input/output error

**URL:** <https://discuss.elastic.co/t/index-merge-scheduler-exception-java-io-ioexception-input-output-error/8350>\
**Category:** Elasticsearch\
**Created:** [July 8, 2012, 7:50pm UTC](https://discuss.elastic.co/t/index-merge-scheduler-exception-java-io-ioexception-input-output-error/8350 "2012-07-08T19:50:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![T\_Vinod\_Gupta](https://avatars.discourse-cdn.com/v4/letter/t/fbc32d/32.png) [@T\_Vinod\_Gupta](https://discuss.elastic.co/u/T_Vinod_Gupta)\
**Post date:** [July 8, 2012, 7:50pm UTC](https://discuss.elastic.co/t/index-merge-scheduler-exception-java-io-ioexception-input-output-error/8350/1 "2012-07-08T19:50:55Z")

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Hi,  
My log files are showing the below exceptions almost at twice a minute  
frequency. what is causing it and how can i fix it?

also, my queries are taking a long time to execute (sometimes take a  
minute). could this be contributing to it somehow?

[2012-07-08 19:44:19,887][WARN][index.merge.scheduler] [] [twitter][4] failed to merge  
java.io.IOException: Input/output error:  
NIOFSIndexInput(path="/media/ephemeral0  
/ES\_data/elasticsearch/nodes/0/indices/twitter/4/index/\_2h29k.tis")  
at  
org.apache.lucene.store.NIOFSDirectory$NIOFSIndexInput.readInternal(N  
IOFSDirectory.java:180)  
at  
org.apache.lucene.store.BufferedIndexInput.refill(BufferedIndexInput.  
java:229)  
at  
org.apache.lucene.store.BufferedIndexInput.readByte(BufferedIndexInput.java:39)  
at org.apache.lucene.store.DataInput.readVInt(DataInput.java:105)  
at  
org.apache.lucene.store.BufferedIndexInput.readVInt(BufferedIndexInput.java:197)  
at org.apache.lucene.index.TermBuffer.read(TermBuffer.java:86)  
at  
org.apache.lucene.index.SegmentTermEnum.next(SegmentTermEnum.java:133)  
at  
org.apache.lucene.index.SegmentMergeInfo.next(SegmentMergeInfo.java:72)  
at  
org.apache.lucene.index.SegmentMerger.mergeTermInfos(SegmentMerger.java:546)  
at  
org.apache.lucene.index.SegmentMerger.mergeTerms(SegmentMerger.java:473)  
at  
org.apache.lucene.index.SegmentMerger.merge(SegmentMerger.java:109)  
at  
org.apache.lucene.index.IndexWriter.mergeMiddle(IndexWriter.java:4295)  
at org.apache.lucene.index.IndexWriter.merge(IndexWriter.java:3940)  
at  
org.apache.lucene.index.ConcurrentMergeScheduler.doMerge(ConcurrentMergeScheduler.java:388)  
at  
org.apache.lucene.index.TrackingConcurrentMergeScheduler.doMerge(TrackingConcurrentMergeScheduler.java:88)  
at  
org.apache.lucene.index.ConcurrentMergeScheduler$MergeThread.run(ConcurrentMergeScheduler.java:456)  
Caused by: java.io.IOException: Input/output error  
at sun.nio.ch.FileDispatcher.pread0(Native Method)  
at sun.nio.ch.FileDispatcher.pread(FileDispatcher.java:49)  
at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:248)  
at sun.nio.ch.IOUtil.read(IOUtil.java:224)  
at sun.nio.ch.FileChannelImpl.read(FileChannelImpl.java:663)  
at  
org.apache.lucene.store.NIOFSDirectory$NIOFSIndexInput.readInternal(NIOFSDirectory.java:162)  
... 15 more

thanks

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 3:21am UTC](https://discuss.elastic.co/t/index-merge-scheduler-exception-java-io-ioexception-input-output-error/8350/2 "2017-07-06T03:21:05Z")

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