Hi, I tried using mapred.map.child.java.opts and mapred.reduce.child.java.opts but looks like hadoop-0.20.2 ingnores it.
On which version have you seen it working? Regards, Vitaliy S On Tue, Oct 5, 2010 at 5:14 PM, Alejandro Abdelnur <[email protected]> wrote: > The following 2 properties should work: > > mapred.map.child.java.opts > mapred.reduce.child.java.opts > > Alejandro > > > On Tue, Oct 5, 2010 at 9:02 PM, Michael Segel <[email protected]> > wrote: >> >> Hi, >> >> You don't say which version of Hadoop you are using. >> Going from memory, I believe in the CDH3 release from Cloudera, there are >> some specific OPTs you can set in hadoop-env.sh. >> >> HTH >> >> -Mike >> >> >>> Date: Tue, 5 Oct 2010 16:59:35 +0400 >>> Subject: how to set diffent VM parameters for mappers and reducers? >>> From: [email protected] >>> To: [email protected] >>> >>> Hello, >>> >>> >>> I have mappers that do not need much ram but combiners and reducers need a >>> lot. >>> Is it possible to set different VM parameters for mappers and reducers? >>> >>> >>> >>> PS Often I face interesting problem, on same set of data I >>> recieve I have java.lang.OutOfMemoryError: Java heap space in combiner >>> but it happens not all the time. >>> What could be cause of such behavior? >>> My personal opinion is that I have >>> >>> mapred.job.reuse.jvm.num.tasks=-1 and jvm GC doesn't always start when >>> it should. >>> >>> Thanks in Advance, >>> Vitaliy S >> >
