Joey, my errors closely resembles this one<http://mail-archives.apache.org/mod_mbox/hadoop-mapreduce-user/201006.mbox/%3caanlktikr3df4ce-tgiphv9_-evfoed_5-t684nf4y...@mail.gmail.com%3E>in the archives. I can now be much more specific with the errors message, and it is quoted below. I tried -Xmx3096. But I got the same error.
Thank you, Mark syslog logs 2012-05-23 20:04:52,349 WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable 2012-05-23 20:04:52,519 INFO org.apache.hadoop.metrics.jvm.JvmMetrics: Initializing JVM Metrics with processName=MAP, sessionId= 2012-05-23 20:04:52,695 INFO org.apache.hadoop.util.ProcessTree: setsid exited with exit code 0 2012-05-23 20:04:52,699 INFO org.apache.hadoop.mapred.Task: Using ResourceCalculatorPlugin : org.apache.hadoop.util.LinuxResourceCalculatorPlugin@d56b37 2012-05-23 20:04:52,813 INFO org.apache.hadoop.mapred.MapTask: io.sort.mb = 100 2012-05-23 20:04:52,998 INFO org.apache.hadoop.mapred.MapTask: data buffer = 79691776/99614720 2012-05-23 20:04:52,998 INFO org.apache.hadoop.mapred.MapTask: record buffer = 262144/327680 2012-05-23 20:04:53,010 WARN org.apache.hadoop.io.compress.snappy.LoadSnappy: Snappy native library not loaded 2012-05-23 20:12:29,120 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:12:29,134 INFO org.apache.hadoop.mapred.MapTask: bufstart = 0; bufend = 79542629; bufvoid = 99614720 2012-05-23 20:12:29,134 INFO org.apache.hadoop.mapred.MapTask: kvstart = 0; kvend = 228; length = 327680 2012-05-23 20:12:31,248 INFO org.apache.hadoop.mapred.MapTask: Finished spill 0 2012-05-23 20:13:01,862 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:13:01,862 INFO org.apache.hadoop.mapred.MapTask: bufstart = 79542629; bufend = 53863940; bufvoid = 99614720 2012-05-23 20:13:01,862 INFO org.apache.hadoop.mapred.MapTask: kvstart = 228; kvend = 431; length = 327680 2012-05-23 20:13:03,294 INFO org.apache.hadoop.mapred.MapTask: Finished spill 1 2012-05-23 20:13:48,121 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:13:48,122 INFO org.apache.hadoop.mapred.MapTask: bufstart = 53863940; bufend = 31696780; bufvoid = 99614720 2012-05-23 20:13:48,122 INFO org.apache.hadoop.mapred.MapTask: kvstart = 431; kvend = 861; length = 327680 2012-05-23 20:13:49,818 INFO org.apache.hadoop.mapred.MapTask: Finished spill 2 2012-05-23 20:15:25,618 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:15:25,618 INFO org.apache.hadoop.mapred.MapTask: bufstart = 31696780; bufend = 10267329; bufvoid = 99614720 2012-05-23 20:15:25,618 INFO org.apache.hadoop.mapred.MapTask: kvstart = 861; kvend = 1462; length = 327680 2012-05-23 20:15:27,068 INFO org.apache.hadoop.mapred.MapTask: Finished spill 3 2012-05-23 20:15:53,519 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:15:53,519 INFO org.apache.hadoop.mapred.MapTask: bufstart = 10267329; bufend = 85241086; bufvoid = 99614720 2012-05-23 20:15:53,519 INFO org.apache.hadoop.mapred.MapTask: kvstart = 1462; kvend = 1642; length = 327680 2012-05-23 20:15:54,760 INFO org.apache.hadoop.mapred.MapTask: Finished spill 4 2012-05-23 20:16:26,284 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:16:26,284 INFO org.apache.hadoop.mapred.MapTask: bufstart = 85241086; bufend = 51305930; bufvoid = 99614720 2012-05-23 20:16:26,284 INFO org.apache.hadoop.mapred.MapTask: kvstart = 1642; kvend = 1946; length = 327680 2012-05-23 20:16:27,566 INFO org.apache.hadoop.mapred.MapTask: Finished spill 5 2012-05-23 20:16:57,046 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:16:57,046 INFO org.apache.hadoop.mapred.MapTask: bufstart = 51305930; bufend = 31353466; bufvoid = 99614720 2012-05-23 20:16:57,046 INFO org.apache.hadoop.mapred.MapTask: kvstart = 1946; kvend = 2263; length = 327680 2012-05-23 20:16:58,076 INFO org.apache.hadoop.mapred.MapTask: Finished spill 6 2012-05-23 20:17:52,820 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:17:52,820 INFO org.apache.hadoop.mapred.MapTask: bufstart = 31353466; bufend = 10945750; bufvoid = 99614720 2012-05-23 20:17:52,820 INFO org.apache.hadoop.mapred.MapTask: kvstart = 2263; kvend = 2755; length = 327680 2012-05-23 20:17:53,939 INFO org.apache.hadoop.mapred.MapTask: Finished spill 7 2012-05-23 20:18:19,528 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:18:19,528 INFO org.apache.hadoop.mapred.MapTask: bufstart = 10945750; bufend = 81838103; bufvoid = 99614720 2012-05-23 20:18:19,528 INFO org.apache.hadoop.mapred.MapTask: kvstart = 2755; kvend = 2967; length = 327680 2012-05-23 20:18:21,145 INFO org.apache.hadoop.mapred.MapTask: Finished spill 8 2012-05-23 20:18:52,353 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:18:52,353 INFO org.apache.hadoop.mapred.MapTask: bufstart = 81838103; bufend = 61751422; bufvoid = 99614720 2012-05-23 20:18:52,353 INFO org.apache.hadoop.mapred.MapTask: kvstart = 2967; kvend = 3202; length = 327680 2012-05-23 20:18:53,485 INFO org.apache.hadoop.mapred.MapTask: Finished spill 9 2012-05-23 20:19:42,993 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:19:42,993 INFO org.apache.hadoop.mapred.MapTask: bufstart = 61751422; bufend = 38440188; bufvoid = 99614720 2012-05-23 20:19:42,993 INFO org.apache.hadoop.mapred.MapTask: kvstart = 3202; kvend = 3628; length = 327680 2012-05-23 20:19:44,346 INFO org.apache.hadoop.mapred.MapTask: Finished spill 10 2012-05-23 20:20:47,957 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:20:47,957 INFO org.apache.hadoop.mapred.MapTask: bufstart = 38440188; bufend = 18376423; bufvoid = 99614720 2012-05-23 20:20:47,957 INFO org.apache.hadoop.mapred.MapTask: kvstart = 3628; kvend = 4252; length = 327680 2012-05-23 20:20:48,767 INFO org.apache.hadoop.mapred.MapTask: Finished spill 11 2012-05-23 20:21:19,207 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:21:19,207 INFO org.apache.hadoop.mapred.MapTask: bufstart = 18376423; bufend = 97890160; bufvoid = 99614720 2012-05-23 20:21:19,207 INFO org.apache.hadoop.mapred.MapTask: kvstart = 4252; kvend = 4488; length = 327680 2012-05-23 20:21:20,176 INFO org.apache.hadoop.mapred.MapTask: Finished spill 12 2012-05-23 20:21:47,395 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:21:47,395 INFO org.apache.hadoop.mapred.MapTask: bufstart = 97890160; bufend = 77234938; bufvoid = 99614720 2012-05-23 20:21:47,395 INFO org.apache.hadoop.mapred.MapTask: kvstart = 4488; kvend = 4771; length = 327680 2012-05-23 20:21:48,383 INFO org.apache.hadoop.mapred.MapTask: Finished spill 13 2012-05-23 20:22:21,086 INFO org.apache.hadoop.mapred.MapTask: Spilling map output: buffer full= true 2012-05-23 20:22:21,086 INFO org.apache.hadoop.mapred.MapTask: bufstart = 77234938; bufend = 52962105; bufvoid = 99614720 2012-05-23 20:22:21,086 INFO org.apache.hadoop.mapred.MapTask: kvstart = 4771; kvend = 5203; length = 327680 2012-05-23 20:22:21,641 INFO org.apache.hadoop.mapred.MapTask: Finished spill 14 2012-05-23 20:22:46,559 INFO org.apache.hadoop.mapred.MapTask: Starting flush of map output 2012-05-23 20:22:46,615 INFO org.apache.hadoop.mapred.MapTask: Finished spill 15 2012-05-23 20:22:47,606 INFO org.apache.hadoop.mapred.Merger: Merging 16 sorted segments 2012-05-23 20:22:47,696 INFO org.apache.hadoop.mapred.Merger: Merging 7 intermediate segments out of a total of 16 2012-05-23 20:22:58,083 INFO org.apache.hadoop.mapred.TaskLogsTruncater: Initializing logs' truncater with mapRetainSize=-1 and reduceRetainSize=-1 2012-05-23 20:22:58,108 FATAL org.apache.hadoop.mapred.Child: Error running child : java.lang.OutOfMemoryError: Java heap space at org.apache.hadoop.mapred.IFile$Reader.readNextBlock(IFile.java:355) at org.apache.hadoop.mapred.IFile$Reader.next(IFile.java:417) at org.apache.hadoop.mapred.Merger$Segment.next(Merger.java:220) at org.apache.hadoop.mapred.Merger$MergeQueue.adjustPriorityQueue(Merger.java:330) at org.apache.hadoop.mapred.Merger$MergeQueue.next(Merger.java:350) at org.apache.hadoop.mapred.Merger.writeFile(Merger.java:156) at org.apache.hadoop.mapred.Merger$MergeQueue.merge(Merger.java:499) at org.apache.hadoop.mapred.Merger$MergeQueue.merge(Merger.java:381) at org.apache.hadoop.mapred.Merger.merge(Merger.java:77) at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.mergeParts(MapTask.java:1548) at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.flush(MapTask.java:1180) at org.apache.hadoop.mapred.MapTask$NewOutputCollector.close(MapTask.java:582) at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:649) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:323) at org.apache.hadoop.mapred.Child$4.run(Child.java:270) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1177) at org.apache.hadoop.mapred.Child.main(Child.java:264) On Wed, May 23, 2012 at 2:47 PM, Joey Krabacher <jkrabac...@gmail.com>wrote: > My experience with this sort of problem tells me one of two things and > maybe both: > > 1. there are some optimizations to the code that can be made (variable > re-creation inside of loops, etc.) > 2. something has gone horribly wrong with the logic in the mapper. > > To troubleshoot I would output some log entries at specific points in the > mapper (be careful not to log every execution of the mapper because this > could cause major issues with the disk filling up and that sort of thing.) > > Hope that helps. > > /* Joey */ > > On Wed, May 23, 2012 at 2:16 PM, Mark Kerzner <mark.kerz...@shmsoft.com > >wrote: > > > Hi, all, > > > > I got the exception below in the mapper. I already have my global Hadoop > > heap at 5 GB, but is there a specific other setting? Or maybe I should > > troubleshoot for memory? > > > > But the same application works in the IDE. > > > > Thank you! > > > > Mark > > > > *stderr logs* > > > > Exception in thread "Thread for syncLogs" java.lang.OutOfMemoryError: > > Java heap space > > at > java.io.BufferedOutputStream.<init>(BufferedOutputStream.java:76) > > at > java.io.BufferedOutputStream.<init>(BufferedOutputStream.java:59) > > at > > org.apache.hadoop.mapred.TaskLog.writeToIndexFile(TaskLog.java:292) > > at org.apache.hadoop.mapred.TaskLog.syncLogs(TaskLog.java:365) > > at org.apache.hadoop.mapred.Child$3.run(Child.java:157) > > Exception in thread "communication thread" java.lang.OutOfMemoryError: > > Java heap space > > > > Exception: java.lang.OutOfMemoryError thrown from the > > UncaughtExceptionHandler in thread "communication thread" > > >