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Re: Now give .gz file as input to the MAP
Rahul-da

I found bz2 pretty slow (although splittable) so I switched to snappy (only sequence files are splittable but compress-decompress is fast)

Thanks
Sanjay

From: Rahul Bhattacharjee <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Reply-To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Date: Tuesday, June 11, 2013 9:53 PM
To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Subject: Re: Now give .gz file as input to the MAP

Nothing special is required for process .gz files using MR. however , as Sanjay mentioned , verify the codec's configured in core-site and another thing to note is that these files are not splittable.

You might want to use bz2 , these are splittable.

Thanks,
Rahul
On Wed, Jun 12, 2013 at 10:14 AM, Sanjay Subramanian <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>> wrote:

hadoopConf.set("mapreduce.job.inputformat.class", "com.wizecommerce.utils.mapred.TextInputFormat");

hadoopConf.set("mapreduce.job.outputformat.class", "com.wizecommerce.utils.mapred.TextOutputFormat");

No special settings required for reading Gzip except these above

I u want to output Gzip
hadoopConf.set("mapreduce.output.fileoutputformat.compress", "true");

hadoopConf.set("mapreduce.output.fileoutputformat.compress.codec", "org.apache.hadoop.io.compress.GzipCodec");
Make sure Gzip codec is defined in core-site.xml
<!-- core-site.xml -->
<property>
    <name>io.compression.codecs</name>
    <value>org.apache.hadoop.io.compress.GzipCodec,org.apache.hadoop.io.compress.DefaultCodec</value>
</property>

I have a question

Why are u using GZIP as input to Map ? These are not splittable…Unless u have to read multilines (like lines between a BEGIN and END block in a log file) and send it as one record to the mapper

Also in Non-splitable Snappy Codec is better

Good Luck
sanjay

From: samir das mohapatra <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Reply-To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Date: Tuesday, June 11, 2013 9:07 PM
To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>, "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>, "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Subject: Now give .gz file as input to the MAP

Hi All,
    Did any one worked on, how to pass the .gz file as  file input for mapreduce job ?

Regards,
samir.

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