# OOM due to merge exception **URL:** \ **Category:** Elasticsearch\ **Created:** [January 13, 2017, 7:04am UTC](https://discuss.elastic.co/t/oom-due-to-merge-exception/71484 "2017-01-13T07:04:13Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Balamurali](https://avatars.discourse-cdn.com/v4/letter/b/90db22/32.png) [@Balamurali](https://discuss.elastic.co/u/Balamurali)\ **Post date:** [January 13, 2017, 7:04am UTC](https://discuss.elastic.co/t/oom-due-to-merge-exception/71484/1 "2017-01-13T07:04:13Z")
Hi all, we are using ES 1.3.7 cluster with 2 data only nodes , 2 master nodes, one data cum master node. last two days , **we getting more OOM frequently due to merge exception**. its is too confusing ,can anyone suggest the solution to overcome it ---
**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\ **Post date:** [January 16, 2017, 12:51am UTC](https://discuss.elastic.co/t/oom-due-to-merge-exception/71484/2 "2017-01-16T00:51:04Z")
Upgrading would help. Otherwise please provide the full error as well as more info on your cluster. ---
**Author:** ![Balamurali](https://avatars.discourse-cdn.com/v4/letter/b/90db22/32.png) [@Balamurali](https://discuss.elastic.co/u/Balamurali)\ **Post date:** [January 16, 2017, 5:19am UTC](https://discuss.elastic.co/t/oom-due-to-merge-exception/71484/3 "2017-01-16T05:19:12Z")
thanks @warkolm we are using 1.5 GB as heapsize for each node. then we getting these errors. [2017-01-12 07:19:27,551][WARN][index.merge.scheduler] [xxxxxx] [yyyyyy][0] failed to merge java.lang.OutOfMemoryError: Java heap space at org.apache.lucene.util.packed.Packed64SingleBlock.(Packed64SingleBlock.java:53) at org.apache.lucene.util.packed.Packed64SingleBlock$Packed64SingleBlock2.(Packed64SingleBlock.java:280) at org.apache.lucene.util.packed.Packed64SingleBlock.create(Packed64SingleBlock.java:223) at org.apache.lucene.util.packed.Packed64SingleBlock.create(Packed64SingleBlock.java:211) at org.apache.lucene.util.packed.PackedInts.getReaderNoHeader(PackedInts.java:784) at org.apache.lucene.codecs.lucene49.Lucene49NormsProducer.loadNorms(Lucene49NormsProducer.java:192) at org.apache.lucene.codecs.lucene49.Lucene49NormsProducer.getNumeric(Lucene49NormsProducer.java:134) at org.apache.lucene.index.SegmentCoreReaders.getNormValues(SegmentCoreReaders.java:176) at org.apache.lucene.index.SegmentReader.getNormValues(SegmentReader.java:592) at org.apache.lucene.index.SegmentMerger.mergeNorms(SegmentMerger.java:248) at org.apache.lucene.index.SegmentMerger.merge(SegmentMerger.java:133) at org.apache.lucene.index.IndexWriter.mergeMiddle(IndexWriter.java:4225) at org.apache.lucene.index.IndexWriter.merge(IndexWriter.java:3820) at org.apache.lucene.index.ConcurrentMergeScheduler.doMerge(ConcurrentMergeScheduler.java:405) at org.apache.lucene.index.TrackingConcurrentMergeScheduler.doMerge(TrackingConcurrentMergeScheduler.java:106) at org.apache.lucene.index.ConcurrentMergeScheduler$MergeThread.run(ConcurrentMergeScheduler.java:482) [2017-01-12 07:19:28,577][WARN][index.engine.internal][xxxxxx] [yyyyyy][0] failed engine [merge exception] [2017-01-12 07:19:30,727][DEBUG][action.admin.cluster.node.stats] [xxxxxxx] failed to execute on node [p7ntM6dKRBSwC\_KyTg8fFQ] org.apache.lucene.store.AlreadyClosedException: this IndexWriter is closed at org.apache.lucene.index.IndexWriter.ensureOpen(IndexWriter.java:700) at org.apache.lucene.index.IndexWriter.ensureOpen(IndexWriter.java:714) at org.apache.lucene.index.IndexWriter.ramBytesUsed(IndexWriter.java:464) at org.elasticsearch.index.engine.internal.InternalEngine.segmentsStats(InternalEngine.java:1167) at org.elasticsearch.index.shard.service.InternalIndexShard.segmentStats(InternalIndexShard.java:540) at org.elasticsearch.action.admin.indices.stats.CommonStats.(CommonStats.java:166) at org.elasticsearch.action.admin.indices.stats.ShardStats.(ShardStats.java:49) at org.elasticsearch.indices.InternalIndicesService.stats(InternalIndicesService.java:209) at org.elasticsearch.node.service.NodeService.stats(NodeService.java:156) at org.elasticsearch.action.admin.cluster.node.stats.TransportNodesStatsAction.nodeOperation(TransportNodesStatsAction.java:95) at org.elasticsearch.action.admin.cluster.node.stats.TransportNodesStatsAction.nodeOperation(TransportNodesStatsAction.java:43) at org.elasticsearch.action.support.nodes.TransportNodesOperationAction$AsyncAction$2.run(TransportNodesOperationAction.java:140) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) [2017-01-12 07:19:30,740][WARN][cluster.action.shard] [xxxxxx] [yyyyyy][0] sending failed shard for [yyyyyy][0], node[p7ntM6dKRBSwC\_KyTg8fFQ], [P], s[STARTED], indexUUID [_na_], reason [engine failure, message [merge exception][MergeException[java.lang.OutOfMemoryError: Java heap space]; nested: OutOfMemoryError[Java heap space]; ]] can you please help us !! ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [February 13, 2017, 5:19am UTC](https://discuss.elastic.co/t/oom-due-to-merge-exception/71484/4 "2017-02-13T05:19:14Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.