All right, I got it. Thank you very much~
2012/9/11 Jagat Singh <jagatsi...@gmail.com> > Just to add the name is depreciated in new Hadoop > Try to find > mapreduce.job.reduces > > > > > On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <bejoy.had...@gmail.com> wrote: > >> Hi Lin >> >> The default values for all the properties are in >> core-default.xml >> hdfs-default.xml and >> mapred-default.xml >> >> >> Regards >> Bejoy KS >> >> >> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <lin.yang.ja...@gmail.com>wrote: >> >>> Hi, Bejoy >>> >>> Thanks for you reply. >>> >>> where could I find the default value of mapred.reduce.tasks ? I have >>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't >>> found it. >>> >>> >>> 2012/9/11 Bejoy Ks <bejoy.had...@gmail.com> >>> >>>> Hi Lin >>>> >>>> The default value for number of reducers is 1 >>>> >>>> <name>mapred.reduce.tasks</name> >>>> <value>1</value> >>>> >>>> It is not determined by data volume. You need to specify the number of >>>> reducers for your mapreduce jobs as per your data volume. >>>> >>>> Regards >>>> Bejoy KS >>>> >>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang >>>> <lin.yang.ja...@gmail.com>wrote: >>>> >>>>> Hi, all >>>>> >>>>> I was wondering what's the default number of reducer if I don't set it >>>>> in configuration? >>>>> >>>>> Will it change dynamically according to the output volume of Mapper? >>>>> >>>>> -- >>>>> YANG, Lin >>>>> >>>>> >>>> >>> >>> >>> -- >>> YANG, Lin >>> >>> >> > -- YANG, Lin
