Last week, I was struggling to run hadoop job(simple wordcount example program comes with hadoop ) on amazon ec2. Jobs were dying saying
" Could not create the Java virtual machine ". It took me a while to figure out that ulimit was the problem. Whirr by default assign ulimit to a constant number but not unlimited. Setting mapred.child.java.opts to any number ( I tried from 64mb to 4096mb on t1.micro instances to m2.4xlarge ) was throwing error.
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