OutOfMemoryError: Cannot create GC thread. Out of system resources

Scott Carey
Subject	Re: OutOfMemoryError: Cannot create GC thread. Out of system resources
Date	Thu, 01 Apr 2010 19:40:54 GMT
The default size of Java's young GC generation is 1/3 of the heap. (-XX:NewRatio defaults to 2) You have told it to use 100MB for in memory file system. There is a default setting of 64MB sort space. if -Xmx is 128M then the above sums to over 200MB and won't fit. Turning down the use of any of the three above could help, or increasing -Xmx. Additionally, when a thread can't be allocated it could potentially be due to a limit on the OS side for file system handles per process or user. On Mar 31, 2010, at 11:48 AM, Edson Ramiro wrote: > Hi all, > > When I run the pi Hadoop sample I get this error: > > 10/03/31 15:46:13 WARN mapred.JobClient: Error reading task outputhttp:// > h04.ctinfra.ufpr.br:50060/tasklog?plaintext=true&taskid=attempt_201003311545_0001_r_000002_0&filter=stdout > 10/03/31 15:46:13 WARN mapred.JobClient: Error reading task outputhttp:// > h04.ctinfra.ufpr.br:50060/tasklog?plaintext=true&taskid=attempt_201003311545_0001_r_000002_0&filter=stderr > 10/03/31 15:46:20 INFO mapred.JobClient: Task Id : > attempt_201003311545_0001_m_000006_1, Status : FAILED > java.io.IOException: Task process exit with nonzero status of 134. > at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:418) > > May be its because the datanode can't create more threads. > > ramiro@lcpad:~/hadoop-0.20.2$ cat > logs/userlogs/attempt_201003311457_0001_r_000001_2/stdout > # > # A fatal error has been detected by the Java Runtime Environment: > # > # java.lang.OutOfMemoryError: Cannot create GC thread. Out of system > resources. > # > # Internal Error (gcTaskThread.cpp:38), pid=28840, tid=140010745776400 > # Error: Cannot create GC thread. Out of system resources. > # > # JRE version: 6.0_17-b04 > # Java VM: Java HotSpot(TM) 64-Bit Server VM (14.3-b01 mixed mode > linux-amd64 ) > # An error report file with more information is saved as: > # > /var-host/tmp/hadoop-ramiro/mapred/local/taskTracker/jobcache/job_201003311457_0001/attempt_201003311457_0001_r_000001_2/work/hs_err_pid28840.log > # > # If you would like to submit a bug report, please visit: > # http://java.sun.com/webapps/bugreport/crash.jsp > # > > I configured the limits bellow, but I'm still getting the same error. > > > fs.inmemory.size.mb > 100 > > > > mapred.child.java.opts > -Xmx128M > > > Do you know what limit should I configure to fix it? > > Thanks in Advance > > Edson Ramiro