Hey everyone, Thanks to your help (especially by Eric & Jerome), I've managed to write my own little demux processor, including a customized mapper & reducer, for my data type. For now, all of my map output is sent to only reduce process (although Chukwa opens 8 different reduce processes in each demux run).
I would like to exploit the whole cluster, and to have multiple reduce processes (same reducer class, of course, just many instances of them). I've tried to do it by setting different values to ChukwaRecordKey.setKey() in my mapper: protected void parse(String recordEntry, OutputCollector<ChukwaRecordKey, ChukwaRecord> output, Reporter reporter) throws Throwable { key = new ChukwaRecordKey(); String *keyStr* = DATA_TYPE + Math.floor((NUM_OF_REDUCERS*Math.random()))+1; ChukwaRecord record = new ChukwaRecord(); this.buildGenericRecord(record, null, timestamp, *keyStr*); key.setKey(*keyStr*); key.setReduceType(ReducerName); .... (record logic).... output.collect(key, record); } Although I have multiple keys, all of the records are still sent to the same reducer process. How can I send records to different processes? Thanks a lot, -- Oded