None of that. I checked the the input file's SequenceFile Header and it says "org.apache.hadoop.io.compress.zlib.BuiltInZlibDeflater"
Kim On Fri, Mar 28, 2014 at 10:34 AM, Hardik Pandya <[email protected]>wrote: > what is your compression format gzip, lzo or snappy > > for lzo final output > > FileOutputFormat.setCompressOutput(conf, true); > FileOutputFormat.setOutputCompressorClass(conf, LzoCodec.class); > > In addition, to make LZO splittable, you need to make a LZO index file. > > > On Thu, Mar 27, 2014 at 8:57 PM, Kim Chew <[email protected]> wrote: > >> Thanks folks. >> >> I am not awared my input data file has been compressed. >> FileOutputFromat.setCompressOutput() is set to true when the file is >> written. 8-( >> >> Kim >> >> >> On Thu, Mar 27, 2014 at 5:46 PM, Mostafa Ead <[email protected]>wrote: >> >>> The following might answer you partially: >>> >>> Input key is not read from HDFS, it is auto generated as the offset of >>> the input value in the input file. I think that is (partially) why read >>> hdfs bytes is smaller than written hdfs bytes. >>> On Mar 27, 2014 1:34 PM, "Kim Chew" <[email protected]> wrote: >>> >>>> I am also wondering if, say, I have two identical timestamp so they are >>>> going to be written to the same file. Does MulitpleOutputs handle >>>> appending? >>>> >>>> Thanks. >>>> >>>> Kim >>>> >>>> >>>> On Thu, Mar 27, 2014 at 12:30 PM, Thomas Bentsen <[email protected]> wrote: >>>> >>>>> Have you checked the content of the files you write? >>>>> >>>>> >>>>> /th >>>>> >>>>> On Thu, 2014-03-27 at 11:43 -0700, Kim Chew wrote: >>>>> > I have a simple M/R job using Mapper only thus no reducer. The mapper >>>>> > read a timestamp from the value, generate a path to the output file >>>>> > and writes the key and value to the output file. >>>>> > >>>>> > >>>>> > The input file is a sequence file, not compressed and stored in the >>>>> > HDFS, it has a size of 162.68 MB. >>>>> > >>>>> > >>>>> > Output also is written as a sequence file. >>>>> > >>>>> > >>>>> > >>>>> > However, after I ran my job, I have two output part files from the >>>>> > mapper. One has a size of 835.12 MB and the other has a size of >>>>> 224.77 >>>>> > MB. So why is the total outputs size is so much larger? Shouldn't it >>>>> > be more or less equal to the input's size of 162.68MB since I just >>>>> > write the key and value passed to mapper to the output? >>>>> > >>>>> > >>>>> > Here is the mapper code snippet, >>>>> > >>>>> > public void map(BytesWritable key, BytesWritable value, Context >>>>> > context) throws IOException, InterruptedException { >>>>> > >>>>> > long timestamp = bytesToInt(value.getBytes(), >>>>> > TIMESTAMP_INDEX);; >>>>> > String tsStr = sdf.format(new Date(timestamp * 1000L)); >>>>> > >>>>> > mos.write(key, value, generateFileName(tsStr)); // mos is a >>>>> > MultipleOutputs object. >>>>> > } >>>>> > >>>>> > private String generateFileName(String key) { >>>>> > return outputDir+"/"+key+"/raw-vectors"; >>>>> > } >>>>> > >>>>> > >>>>> > And here are the job outputs, >>>>> > >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Launched map tasks=2 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Data-local map tasks=2 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: SLOTS_MILLIS_REDUCES=0 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: File Output Format >>>>> > Counters >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Bytes Written=0 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: FileSystemCounters >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: >>>>> HDFS_BYTES_READ=171086386 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: FILE_BYTES_WRITTEN=54272 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: >>>>> > HDFS_BYTES_WRITTEN=1111374798 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: File Input Format Counters >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Bytes Read=170782415 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Map-Reduce Framework >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Map input records=547 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Physical memory (bytes) >>>>> > snapshot=166428672 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Spilled Records=0 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Total committed heap >>>>> > usage (bytes)=38351872 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: CPU time spent >>>>> (ms)=20080 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Virtual memory (bytes) >>>>> > snapshot=1240104960 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: SPLIT_RAW_BYTES=286 >>>>> > 14/03/27 11:00:56 INFO mapred.JobClient: Map output records=0 >>>>> > >>>>> > >>>>> > TIA, >>>>> > >>>>> > >>>>> > Kim >>>>> > >>>>> >>>>> >>>>> >>>> >> >
