No reducers can't access mapper counters. ---> maybe theres a way to intermediately put counters in the distributed cache???
Jay Vyas MMSB UCHC On Apr 20, 2012, at 1:24 PM, Robert Evans <ev...@yahoo-inc.com> wrote: > There was a discussion about this several months ago > > http://mail-archives.apache.org/mod_mbox/hadoop-mapreduce-user/201112.mbox/%3CCADYHM8xiw8_bF=zqe-bagdfz6r3tob0aof9viozgtzeqgkp...@mail.gmail.com%3E > > The conclusion is that if you want to read them from the reducer you are > going to have to do something special until someone finds time to implement > it as part of. > > https://issues.apache.org/jira/browse/MAPREDUCE-3520 > > --Bobby Evans > > > On 4/20/12 11:36 AM, "Amith D K" <amit...@huawei.com> wrote: > > Yes U can use user defined counter as Jagat suggeted. > > Counter can be enum as Jagat described or any string which are called dynamic > counters. > > It is easier to use Enum counter than dynamic counters, finally it depends on > your use case :) > > Amith > ________________________________________ > From: Jagat [jagatsi...@gmail.com] > Sent: Saturday, April 21, 2012 12:25 AM > To: common-user@hadoop.apache.org > Subject: Re: Accessing global Counters > > Hi > > You can create your own counters like > > enum CountFruits { > Apple, > Mango, > Banana > } > > > And in your mapper class when you see condition to increment , you can use > Reporter incrCounter method to do the same. > > http://hadoop.apache.org/common/docs/current/api/org/apache/hadoop/mapred/Reporter.html#incrCounter(java.lang.Enum,%20long) > > e.g > // I saw Apple increment it by one > reporter.incrCounter(CountFruits.Apple,1); > > Now you can access them using job.getCounters > > http://hadoop.apache.org/common/docs/current/api/org/apache/hadoop/mapreduce/Job.html#getCounters() > > Hope this helps > > Regards, > > Jagat Singh > > > On Fri, Apr 20, 2012 at 9:43 PM, Gayatri Rao <rgayat...@gmail.com> wrote: > >> Hi All, >> >> Is there a way for me to set global counters in Mapper and access them from >> reducer? >> Could you suggest how I can acheve this? >> >> Thanks >> Gayatri >> >
