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Posted to user@whirr.apache.org by Paolo Castagna <ca...@googlemail.com> on 2011/10/07 14:56:55 UTC
WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Hi,
I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20 nodes)
Hadoop clusters on Amazon EC2 for testing.
In my hadoop-ec2.properties I have:
whirr.hardware-id=m1.large
# See http://alestic.com/
whirr.image-id=eu-west-1/ami-8293a5f6
whirr.location-id=eu-west-1
whirr.hadoop.version=0.20.204.0
whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
I am able to successfully run MapReduce jobs but I see errors as soon as I
try to enable compression (either for the map output or for the SequenceFile
at the end of a job).
In the task logs I see this warning, which I think is relevant:
WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform... using builtin-java classes
where applicable
This is what I have in my "driver(s)", for the intermediate map output:
if ( useCompression ) {
configuration.setBoolean("mapred.compress.map.output", true);
configuration.set("mapred.output.compression.type", "BLOCK");
configuration.set("mapred.map.output.compression.codec",
"org.apache.hadoop.io.compress.GzipCodec");
}
For the final job output:
if ( useCompression ) {
SequenceFileOutputFormat.setCompressOutput(job, true);
SequenceFileOutputFormat.setOutputCompressorClass(job, GzipCodec.class);
SequenceFileOutputFormat.setOutputCompressionType(job,
CompressionType.BLOCK);
}
As you can see I am trying to use a simple GzipCodec, nothing strange.
What am I doing wrong?
What should I do in order to be able to use compression in my MapReduce jobs?
Thank you in advance for your help,
Paolo
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Paolo Castagna <ca...@googlemail.com>.
Hi Tom,
thanks for your reply (and sorry for the late response).
It's good to know that "it should just work".
Even if it doesn't with 0.20.204.0... it certainly is the right attitude!
No, I did not tried with Hadoop 0.20.2.
I am using 0.20.204.0 and, right now, I am not sure if I need need code
changes to try with 0.20.2. If I try with 0.20.2, I'll let you know.
Paolo
Tom White wrote:
> The native libraries should be already built for Linux and included in
> the tarball, and should just work. Do you have the same problem when
> running Hadoop 0.20.2 with Whirr?
>
> Tom
>
> On Fri, Oct 7, 2011 at 7:19 AM, Paolo Castagna
> <ca...@googlemail.com> wrote:
>> Hi Andrei,
>> probably you are right, there is something you need to do when you
>> install an Hadoop cluster to support compression:
>> http://hadoop.apache.org/common/docs/current/native_libraries.html
>>
>> However, it would be nice if Whirr could do that and make compression
>> available to developers.
>>
>> I am now going to try to use the DistributedCache to distribute the
>> necessary shared libraries:
>> http://hadoop.apache.org/common/docs/current/native_libraries.html#Native+Shared+Libraries
>>
>> If others are using compression with cluster created via Apache Whirr
>> I am interested to know what they are doing.
>>
>> Thanks,
>> Paolo
>>
>> On 7 October 2011 15:09, Andrei Savu <sa...@gmail.com> wrote:
>>> Ask on the Hadoop email list if the official release supports compression
>>> out of the box.
>>>
>>> On Oct 7, 2011 5:00 PM, "Paolo Castagna" <ca...@googlemail.com>
>>> wrote:
>>>> Hi Andrei,
>>>> thank you for your reply.
>>>>
>>>> As I wrote in my previous message, I have this in my hadoop-ec2.properties
>>>> file:
>>>> whirr.hadoop.version=0.20.204.0
>>>>
>>>> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>>>
>>>> Therefore I am using Apache Hadoop release 0.20.204.0.
>>>>
>>>> Can anyone confirm that you cannot use compression with Hadoop
>>>> clusters installed via Whirr?
>>>>
>>>> Paolo
>>>>
>>>> On 7 October 2011 14:23, Andrei Savu <sa...@gmail.com> wrote:
>>>>> I am not sure but I think you need a custom Hadoop build to support
>>>>> compression. Are you using the Apache release or CDH?
>>>>>
>>>>> On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
>>>>> wrote:
>>>>>> Hi,
>>>>>> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20
>>>>>> nodes)
>>>>>> Hadoop clusters on Amazon EC2 for testing.
>>>>>>
>>>>>> In my hadoop-ec2.properties I have:
>>>>>>
>>>>>> whirr.hardware-id=m1.large
>>>>>> # See http://alestic.com/
>>>>>> whirr.image-id=eu-west-1/ami-8293a5f6
>>>>>> whirr.location-id=eu-west-1
>>>>>> whirr.hadoop.version=0.20.204.0
>>>>>>
>>>>>>
>>>>>> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>>>>>
>>>>>> I am able to successfully run MapReduce jobs but I see errors as soon
>>>>>> as I
>>>>>> try to enable compression (either for the map output or for the
>>>>>> SequenceFile
>>>>>> at the end of a job).
>>>>>>
>>>>>> In the task logs I see this warning, which I think is relevant:
>>>>>> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
>>>>>> native-hadoop library for your platform... using builtin-java classes
>>>>>> where applicable
>>>>>>
>>>>>> This is what I have in my "driver(s)", for the intermediate map output:
>>>>>>
>>>>>> if ( useCompression ) {
>>>>>> configuration.setBoolean("mapred.compress.map.output", true);
>>>>>> configuration.set("mapred.output.compression.type", "BLOCK");
>>>>>> configuration.set("mapred.map.output.compression.codec",
>>>>>> "org.apache.hadoop.io.compress.GzipCodec");
>>>>>> }
>>>>>>
>>>>>> For the final job output:
>>>>>>
>>>>>> if ( useCompression ) {
>>>>>> SequenceFileOutputFormat.setCompressOutput(job, true);
>>>>>> SequenceFileOutputFormat.setOutputCompressorClass(job,
>>>>>> GzipCodec.class);
>>>>>> SequenceFileOutputFormat.setOutputCompressionType(job,
>>>>>> CompressionType.BLOCK);
>>>>>> }
>>>>>>
>>>>>> As you can see I am trying to use a simple GzipCodec, nothing strange.
>>>>>>
>>>>>> What am I doing wrong?
>>>>>> What should I do in order to be able to use compression in my MapReduce
>>>>>> jobs?
>>>>>>
>>>>>> Thank you in advance for your help,
>>>>>> Paolo
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Tom White <to...@cloudera.com>.
The native libraries should be already built for Linux and included in
the tarball, and should just work. Do you have the same problem when
running Hadoop 0.20.2 with Whirr?
Tom
On Fri, Oct 7, 2011 at 7:19 AM, Paolo Castagna
<ca...@googlemail.com> wrote:
> Hi Andrei,
> probably you are right, there is something you need to do when you
> install an Hadoop cluster to support compression:
> http://hadoop.apache.org/common/docs/current/native_libraries.html
>
> However, it would be nice if Whirr could do that and make compression
> available to developers.
>
> I am now going to try to use the DistributedCache to distribute the
> necessary shared libraries:
> http://hadoop.apache.org/common/docs/current/native_libraries.html#Native+Shared+Libraries
>
> If others are using compression with cluster created via Apache Whirr
> I am interested to know what they are doing.
>
> Thanks,
> Paolo
>
> On 7 October 2011 15:09, Andrei Savu <sa...@gmail.com> wrote:
>> Ask on the Hadoop email list if the official release supports compression
>> out of the box.
>>
>> On Oct 7, 2011 5:00 PM, "Paolo Castagna" <ca...@googlemail.com>
>> wrote:
>>>
>>> Hi Andrei,
>>> thank you for your reply.
>>>
>>> As I wrote in my previous message, I have this in my hadoop-ec2.properties
>>> file:
>>> whirr.hadoop.version=0.20.204.0
>>>
>>> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>>
>>> Therefore I am using Apache Hadoop release 0.20.204.0.
>>>
>>> Can anyone confirm that you cannot use compression with Hadoop
>>> clusters installed via Whirr?
>>>
>>> Paolo
>>>
>>> On 7 October 2011 14:23, Andrei Savu <sa...@gmail.com> wrote:
>>> > I am not sure but I think you need a custom Hadoop build to support
>>> > compression. Are you using the Apache release or CDH?
>>> >
>>> > On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
>>> > wrote:
>>> >>
>>> >> Hi,
>>> >> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20
>>> >> nodes)
>>> >> Hadoop clusters on Amazon EC2 for testing.
>>> >>
>>> >> In my hadoop-ec2.properties I have:
>>> >>
>>> >> whirr.hardware-id=m1.large
>>> >> # See http://alestic.com/
>>> >> whirr.image-id=eu-west-1/ami-8293a5f6
>>> >> whirr.location-id=eu-west-1
>>> >> whirr.hadoop.version=0.20.204.0
>>> >>
>>> >>
>>> >> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>> >>
>>> >> I am able to successfully run MapReduce jobs but I see errors as soon
>>> >> as I
>>> >> try to enable compression (either for the map output or for the
>>> >> SequenceFile
>>> >> at the end of a job).
>>> >>
>>> >> In the task logs I see this warning, which I think is relevant:
>>> >> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
>>> >> native-hadoop library for your platform... using builtin-java classes
>>> >> where applicable
>>> >>
>>> >> This is what I have in my "driver(s)", for the intermediate map output:
>>> >>
>>> >> if ( useCompression ) {
>>> >> configuration.setBoolean("mapred.compress.map.output", true);
>>> >> configuration.set("mapred.output.compression.type", "BLOCK");
>>> >> configuration.set("mapred.map.output.compression.codec",
>>> >> "org.apache.hadoop.io.compress.GzipCodec");
>>> >> }
>>> >>
>>> >> For the final job output:
>>> >>
>>> >> if ( useCompression ) {
>>> >> SequenceFileOutputFormat.setCompressOutput(job, true);
>>> >> SequenceFileOutputFormat.setOutputCompressorClass(job,
>>> >> GzipCodec.class);
>>> >> SequenceFileOutputFormat.setOutputCompressionType(job,
>>> >> CompressionType.BLOCK);
>>> >> }
>>> >>
>>> >> As you can see I am trying to use a simple GzipCodec, nothing strange.
>>> >>
>>> >> What am I doing wrong?
>>> >> What should I do in order to be able to use compression in my MapReduce
>>> >> jobs?
>>> >>
>>> >> Thank you in advance for your help,
>>> >> Paolo
>>> >
>>
>
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Paolo Castagna <ca...@googlemail.com>.
Hi Andrei,
probably you are right, there is something you need to do when you
install an Hadoop cluster to support compression:
http://hadoop.apache.org/common/docs/current/native_libraries.html
However, it would be nice if Whirr could do that and make compression
available to developers.
I am now going to try to use the DistributedCache to distribute the
necessary shared libraries:
http://hadoop.apache.org/common/docs/current/native_libraries.html#Native+Shared+Libraries
If others are using compression with cluster created via Apache Whirr
I am interested to know what they are doing.
Thanks,
Paolo
On 7 October 2011 15:09, Andrei Savu <sa...@gmail.com> wrote:
> Ask on the Hadoop email list if the official release supports compression
> out of the box.
>
> On Oct 7, 2011 5:00 PM, "Paolo Castagna" <ca...@googlemail.com>
> wrote:
>>
>> Hi Andrei,
>> thank you for your reply.
>>
>> As I wrote in my previous message, I have this in my hadoop-ec2.properties
>> file:
>> whirr.hadoop.version=0.20.204.0
>>
>> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>
>> Therefore I am using Apache Hadoop release 0.20.204.0.
>>
>> Can anyone confirm that you cannot use compression with Hadoop
>> clusters installed via Whirr?
>>
>> Paolo
>>
>> On 7 October 2011 14:23, Andrei Savu <sa...@gmail.com> wrote:
>> > I am not sure but I think you need a custom Hadoop build to support
>> > compression. Are you using the Apache release or CDH?
>> >
>> > On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
>> > wrote:
>> >>
>> >> Hi,
>> >> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20
>> >> nodes)
>> >> Hadoop clusters on Amazon EC2 for testing.
>> >>
>> >> In my hadoop-ec2.properties I have:
>> >>
>> >> whirr.hardware-id=m1.large
>> >> # See http://alestic.com/
>> >> whirr.image-id=eu-west-1/ami-8293a5f6
>> >> whirr.location-id=eu-west-1
>> >> whirr.hadoop.version=0.20.204.0
>> >>
>> >>
>> >> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>> >>
>> >> I am able to successfully run MapReduce jobs but I see errors as soon
>> >> as I
>> >> try to enable compression (either for the map output or for the
>> >> SequenceFile
>> >> at the end of a job).
>> >>
>> >> In the task logs I see this warning, which I think is relevant:
>> >> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
>> >> native-hadoop library for your platform... using builtin-java classes
>> >> where applicable
>> >>
>> >> This is what I have in my "driver(s)", for the intermediate map output:
>> >>
>> >> if ( useCompression ) {
>> >> configuration.setBoolean("mapred.compress.map.output", true);
>> >> configuration.set("mapred.output.compression.type", "BLOCK");
>> >> configuration.set("mapred.map.output.compression.codec",
>> >> "org.apache.hadoop.io.compress.GzipCodec");
>> >> }
>> >>
>> >> For the final job output:
>> >>
>> >> if ( useCompression ) {
>> >> SequenceFileOutputFormat.setCompressOutput(job, true);
>> >> SequenceFileOutputFormat.setOutputCompressorClass(job,
>> >> GzipCodec.class);
>> >> SequenceFileOutputFormat.setOutputCompressionType(job,
>> >> CompressionType.BLOCK);
>> >> }
>> >>
>> >> As you can see I am trying to use a simple GzipCodec, nothing strange.
>> >>
>> >> What am I doing wrong?
>> >> What should I do in order to be able to use compression in my MapReduce
>> >> jobs?
>> >>
>> >> Thank you in advance for your help,
>> >> Paolo
>> >
>
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Andrei Savu <sa...@gmail.com>.
Ask on the Hadoop email list if the official release supports compression
out of the box.
On Oct 7, 2011 5:00 PM, "Paolo Castagna" <ca...@googlemail.com>
wrote:
> Hi Andrei,
> thank you for your reply.
>
> As I wrote in my previous message, I have this in my hadoop-ec2.properties
> file:
> whirr.hadoop.version=0.20.204.0
> whirr.hadoop.tarball.url=
> http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>
> Therefore I am using Apache Hadoop release 0.20.204.0.
>
> Can anyone confirm that you cannot use compression with Hadoop
> clusters installed via Whirr?
>
> Paolo
>
> On 7 October 2011 14:23, Andrei Savu <sa...@gmail.com> wrote:
> > I am not sure but I think you need a custom Hadoop build to support
> > compression. Are you using the Apache release or CDH?
> >
> > On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
> > wrote:
> >>
> >> Hi,
> >> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20
> >> nodes)
> >> Hadoop clusters on Amazon EC2 for testing.
> >>
> >> In my hadoop-ec2.properties I have:
> >>
> >> whirr.hardware-id=m1.large
> >> # See http://alestic.com/
> >> whirr.image-id=eu-west-1/ami-8293a5f6
> >> whirr.location-id=eu-west-1
> >> whirr.hadoop.version=0.20.204.0
> >>
> >> whirr.hadoop.tarball.url=
> http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
> >>
> >> I am able to successfully run MapReduce jobs but I see errors as soon as
> I
> >> try to enable compression (either for the map output or for the
> >> SequenceFile
> >> at the end of a job).
> >>
> >> In the task logs I see this warning, which I think is relevant:
> >> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
> >> native-hadoop library for your platform... using builtin-java classes
> >> where applicable
> >>
> >> This is what I have in my "driver(s)", for the intermediate map output:
> >>
> >> if ( useCompression ) {
> >> configuration.setBoolean("mapred.compress.map.output", true);
> >> configuration.set("mapred.output.compression.type", "BLOCK");
> >> configuration.set("mapred.map.output.compression.codec",
> >> "org.apache.hadoop.io.compress.GzipCodec");
> >> }
> >>
> >> For the final job output:
> >>
> >> if ( useCompression ) {
> >> SequenceFileOutputFormat.setCompressOutput(job, true);
> >> SequenceFileOutputFormat.setOutputCompressorClass(job,
> >> GzipCodec.class);
> >> SequenceFileOutputFormat.setOutputCompressionType(job,
> >> CompressionType.BLOCK);
> >> }
> >>
> >> As you can see I am trying to use a simple GzipCodec, nothing strange.
> >>
> >> What am I doing wrong?
> >> What should I do in order to be able to use compression in my MapReduce
> >> jobs?
> >>
> >> Thank you in advance for your help,
> >> Paolo
> >
>
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Paolo Castagna <ca...@googlemail.com>.
Hi Andrei,
thank you for your reply.
As I wrote in my previous message, I have this in my hadoop-ec2.properties file:
whirr.hadoop.version=0.20.204.0
whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
Therefore I am using Apache Hadoop release 0.20.204.0.
Can anyone confirm that you cannot use compression with Hadoop
clusters installed via Whirr?
Paolo
On 7 October 2011 14:23, Andrei Savu <sa...@gmail.com> wrote:
> I am not sure but I think you need a custom Hadoop build to support
> compression. Are you using the Apache release or CDH?
>
> On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
> wrote:
>>
>> Hi,
>> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20
>> nodes)
>> Hadoop clusters on Amazon EC2 for testing.
>>
>> In my hadoop-ec2.properties I have:
>>
>> whirr.hardware-id=m1.large
>> # See http://alestic.com/
>> whirr.image-id=eu-west-1/ami-8293a5f6
>> whirr.location-id=eu-west-1
>> whirr.hadoop.version=0.20.204.0
>>
>> whirr.hadoop.tarball.url=http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>>
>> I am able to successfully run MapReduce jobs but I see errors as soon as I
>> try to enable compression (either for the map output or for the
>> SequenceFile
>> at the end of a job).
>>
>> In the task logs I see this warning, which I think is relevant:
>> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
>> native-hadoop library for your platform... using builtin-java classes
>> where applicable
>>
>> This is what I have in my "driver(s)", for the intermediate map output:
>>
>> if ( useCompression ) {
>> configuration.setBoolean("mapred.compress.map.output", true);
>> configuration.set("mapred.output.compression.type", "BLOCK");
>> configuration.set("mapred.map.output.compression.codec",
>> "org.apache.hadoop.io.compress.GzipCodec");
>> }
>>
>> For the final job output:
>>
>> if ( useCompression ) {
>> SequenceFileOutputFormat.setCompressOutput(job, true);
>> SequenceFileOutputFormat.setOutputCompressorClass(job,
>> GzipCodec.class);
>> SequenceFileOutputFormat.setOutputCompressionType(job,
>> CompressionType.BLOCK);
>> }
>>
>> As you can see I am trying to use a simple GzipCodec, nothing strange.
>>
>> What am I doing wrong?
>> What should I do in order to be able to use compression in my MapReduce
>> jobs?
>>
>> Thank you in advance for your help,
>> Paolo
>
Re: WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
native-hadoop library for your platform...
Posted by Andrei Savu <sa...@gmail.com>.
I am not sure but I think you need a custom Hadoop build to support
compression. Are you using the Apache release or CDH?
On Oct 7, 2011 3:57 PM, "Paolo Castagna" <ca...@googlemail.com>
wrote:
> Hi,
> I am using Apache Whirr 0.6.0-incubating to create small (i.e. 10-20 nodes)
> Hadoop clusters on Amazon EC2 for testing.
>
> In my hadoop-ec2.properties I have:
>
> whirr.hardware-id=m1.large
> # See http://alestic.com/
> whirr.image-id=eu-west-1/ami-8293a5f6
> whirr.location-id=eu-west-1
> whirr.hadoop.version=0.20.204.0
> whirr.hadoop.tarball.url=
> http://archive.apache.org/dist/hadoop/core/hadoop-${whirr.hadoop.version}/hadoop-${whirr.hadoop.version}.tar.gz
>
> I am able to successfully run MapReduce jobs but I see errors as soon as I
> try to enable compression (either for the map output or for the
> SequenceFile
> at the end of a job).
>
> In the task logs I see this warning, which I think is relevant:
> WARN org.apache.hadoop.util.NativeCodeLoader: Unable to load
> native-hadoop library for your platform... using builtin-java classes
> where applicable
>
> This is what I have in my "driver(s)", for the intermediate map output:
>
> if ( useCompression ) {
> configuration.setBoolean("mapred.compress.map.output", true);
> configuration.set("mapred.output.compression.type", "BLOCK");
> configuration.set("mapred.map.output.compression.codec",
> "org.apache.hadoop.io.compress.GzipCodec");
> }
>
> For the final job output:
>
> if ( useCompression ) {
> SequenceFileOutputFormat.setCompressOutput(job, true);
> SequenceFileOutputFormat.setOutputCompressorClass(job,
> GzipCodec.class);
> SequenceFileOutputFormat.setOutputCompressionType(job,
> CompressionType.BLOCK);
> }
>
> As you can see I am trying to use a simple GzipCodec, nothing strange.
>
> What am I doing wrong?
> What should I do in order to be able to use compression in my MapReduce
> jobs?
>
> Thank you in advance for your help,
> Paolo
>