1.0.1 On Tue, Nov 13, 2012 at 10:18 AM, Serge Blazhiyevskyy < [email protected]> wrote:
> What hadoop version are we talking about? > > From: Mark Kerzner <[email protected]<mailto: > [email protected]>> > Reply-To: "[email protected]<mailto:[email protected]>" < > [email protected]<mailto:[email protected]>> > Date: Tuesday, November 13, 2012 5:16 PM > To: Hadoop User <[email protected]<mailto:[email protected]>> > Subject: mapred.tasktracker.map.tasks.maximum > > Hi, > > I have a cluster with 4 nodes and 32 many cores on each. My default value > for the maximum number of mappers per slot is 1: > > <property> > <name>mapred.tasktracker.map.tasks.maximum</name> > <!-- see other kb entry about this one. --> > <value>1</value> > <final>true</final> > </property> > (which I think is wrong). > > Howeve, when sizable jobs run, I see 65 mappers working, so it seems that > it does create more than 1 mapper per node. > > Questions: what maximum number of mappers would be appropriate in this > situation? Is that the right way to set them? > > Thank you. Sincerely, > Mark >
