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Posted to user@hadoop.apache.org by Jason Yang <li...@gmail.com> on 2012/09/11 13:23:09 UTC
what's the default reducer number?
Hi, all
I was wondering what's the default number of reducer if I don't set it in
configuration?
Will it change dynamically according to the output volume of Mapper?
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
All right, I got it.
Thank you very much~
2012/9/11 Jagat Singh <ja...@gmail.com>
> Just to add the name is depreciated in new Hadoop
> Try to find
> mapreduce.job.reduces
>
>
>
>
> On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
>
>> Hi Lin
>>
>> The default values for all the properties are in
>> core-default.xml
>> hdfs-default.xml and
>> mapred-default.xml
>>
>>
>> Regards
>> Bejoy KS
>>
>>
>> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, Bejoy
>>>
>>> Thanks for you reply.
>>>
>>> where could I find the default value of mapred.reduce.tasks ? I have
>>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>>> found it.
>>>
>>>
>>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>>
>>>> Hi Lin
>>>>
>>>> The default value for number of reducers is 1
>>>>
>>>> <name>mapred.reduce.tasks</name>
>>>> <value>1</value>
>>>>
>>>> It is not determined by data volume. You need to specify the number of
>>>> reducers for your mapreduce jobs as per your data volume.
>>>>
>>>> Regards
>>>> Bejoy KS
>>>>
>>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>>
>>>>> Hi, all
>>>>>
>>>>> I was wondering what's the default number of reducer if I don't set it
>>>>> in configuration?
>>>>>
>>>>> Will it change dynamically according to the output volume of Mapper?
>>>>>
>>>>> --
>>>>> YANG, Lin
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
All right, I got it.
Thank you very much~
2012/9/11 Jagat Singh <ja...@gmail.com>
> Just to add the name is depreciated in new Hadoop
> Try to find
> mapreduce.job.reduces
>
>
>
>
> On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
>
>> Hi Lin
>>
>> The default values for all the properties are in
>> core-default.xml
>> hdfs-default.xml and
>> mapred-default.xml
>>
>>
>> Regards
>> Bejoy KS
>>
>>
>> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, Bejoy
>>>
>>> Thanks for you reply.
>>>
>>> where could I find the default value of mapred.reduce.tasks ? I have
>>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>>> found it.
>>>
>>>
>>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>>
>>>> Hi Lin
>>>>
>>>> The default value for number of reducers is 1
>>>>
>>>> <name>mapred.reduce.tasks</name>
>>>> <value>1</value>
>>>>
>>>> It is not determined by data volume. You need to specify the number of
>>>> reducers for your mapreduce jobs as per your data volume.
>>>>
>>>> Regards
>>>> Bejoy KS
>>>>
>>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>>
>>>>> Hi, all
>>>>>
>>>>> I was wondering what's the default number of reducer if I don't set it
>>>>> in configuration?
>>>>>
>>>>> Will it change dynamically according to the output volume of Mapper?
>>>>>
>>>>> --
>>>>> YANG, Lin
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
All right, I got it.
Thank you very much~
2012/9/11 Jagat Singh <ja...@gmail.com>
> Just to add the name is depreciated in new Hadoop
> Try to find
> mapreduce.job.reduces
>
>
>
>
> On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
>
>> Hi Lin
>>
>> The default values for all the properties are in
>> core-default.xml
>> hdfs-default.xml and
>> mapred-default.xml
>>
>>
>> Regards
>> Bejoy KS
>>
>>
>> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, Bejoy
>>>
>>> Thanks for you reply.
>>>
>>> where could I find the default value of mapred.reduce.tasks ? I have
>>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>>> found it.
>>>
>>>
>>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>>
>>>> Hi Lin
>>>>
>>>> The default value for number of reducers is 1
>>>>
>>>> <name>mapred.reduce.tasks</name>
>>>> <value>1</value>
>>>>
>>>> It is not determined by data volume. You need to specify the number of
>>>> reducers for your mapreduce jobs as per your data volume.
>>>>
>>>> Regards
>>>> Bejoy KS
>>>>
>>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>>
>>>>> Hi, all
>>>>>
>>>>> I was wondering what's the default number of reducer if I don't set it
>>>>> in configuration?
>>>>>
>>>>> Will it change dynamically according to the output volume of Mapper?
>>>>>
>>>>> --
>>>>> YANG, Lin
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
All right, I got it.
Thank you very much~
2012/9/11 Jagat Singh <ja...@gmail.com>
> Just to add the name is depreciated in new Hadoop
> Try to find
> mapreduce.job.reduces
>
>
>
>
> On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
>
>> Hi Lin
>>
>> The default values for all the properties are in
>> core-default.xml
>> hdfs-default.xml and
>> mapred-default.xml
>>
>>
>> Regards
>> Bejoy KS
>>
>>
>> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, Bejoy
>>>
>>> Thanks for you reply.
>>>
>>> where could I find the default value of mapred.reduce.tasks ? I have
>>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>>> found it.
>>>
>>>
>>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>>
>>>> Hi Lin
>>>>
>>>> The default value for number of reducers is 1
>>>>
>>>> <name>mapred.reduce.tasks</name>
>>>> <value>1</value>
>>>>
>>>> It is not determined by data volume. You need to specify the number of
>>>> reducers for your mapreduce jobs as per your data volume.
>>>>
>>>> Regards
>>>> Bejoy KS
>>>>
>>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>>
>>>>> Hi, all
>>>>>
>>>>> I was wondering what's the default number of reducer if I don't set it
>>>>> in configuration?
>>>>>
>>>>> Will it change dynamically according to the output volume of Mapper?
>>>>>
>>>>> --
>>>>> YANG, Lin
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jagat Singh <ja...@gmail.com>.
Just to add the name is depreciated in new Hadoop
Try to find
mapreduce.job.reduces
On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
> Hi Lin
>
> The default values for all the properties are in
> core-default.xml
> hdfs-default.xml and
> mapred-default.xml
>
>
> Regards
> Bejoy KS
>
>
> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, Bejoy
>>
>> Thanks for you reply.
>>
>> where could I find the default value of mapred.reduce.tasks ? I have
>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>> found it.
>>
>>
>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>
>>> Hi Lin
>>>
>>> The default value for number of reducers is 1
>>>
>>> <name>mapred.reduce.tasks</name>
>>> <value>1</value>
>>>
>>> It is not determined by data volume. You need to specify the number of
>>> reducers for your mapreduce jobs as per your data volume.
>>>
>>> Regards
>>> Bejoy KS
>>>
>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>
>>>> Hi, all
>>>>
>>>> I was wondering what's the default number of reducer if I don't set it
>>>> in configuration?
>>>>
>>>> Will it change dynamically according to the output volume of Mapper?
>>>>
>>>> --
>>>> YANG, Lin
>>>>
>>>>
>>>
>>
>>
>> --
>> YANG, Lin
>>
>>
>
Re: what's the default reducer number?
Posted by Jagat Singh <ja...@gmail.com>.
Just to add the name is depreciated in new Hadoop
Try to find
mapreduce.job.reduces
On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
> Hi Lin
>
> The default values for all the properties are in
> core-default.xml
> hdfs-default.xml and
> mapred-default.xml
>
>
> Regards
> Bejoy KS
>
>
> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, Bejoy
>>
>> Thanks for you reply.
>>
>> where could I find the default value of mapred.reduce.tasks ? I have
>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>> found it.
>>
>>
>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>
>>> Hi Lin
>>>
>>> The default value for number of reducers is 1
>>>
>>> <name>mapred.reduce.tasks</name>
>>> <value>1</value>
>>>
>>> It is not determined by data volume. You need to specify the number of
>>> reducers for your mapreduce jobs as per your data volume.
>>>
>>> Regards
>>> Bejoy KS
>>>
>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>
>>>> Hi, all
>>>>
>>>> I was wondering what's the default number of reducer if I don't set it
>>>> in configuration?
>>>>
>>>> Will it change dynamically according to the output volume of Mapper?
>>>>
>>>> --
>>>> YANG, Lin
>>>>
>>>>
>>>
>>
>>
>> --
>> YANG, Lin
>>
>>
>
Re: what's the default reducer number?
Posted by Jagat Singh <ja...@gmail.com>.
Just to add the name is depreciated in new Hadoop
Try to find
mapreduce.job.reduces
On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
> Hi Lin
>
> The default values for all the properties are in
> core-default.xml
> hdfs-default.xml and
> mapred-default.xml
>
>
> Regards
> Bejoy KS
>
>
> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, Bejoy
>>
>> Thanks for you reply.
>>
>> where could I find the default value of mapred.reduce.tasks ? I have
>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>> found it.
>>
>>
>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>
>>> Hi Lin
>>>
>>> The default value for number of reducers is 1
>>>
>>> <name>mapred.reduce.tasks</name>
>>> <value>1</value>
>>>
>>> It is not determined by data volume. You need to specify the number of
>>> reducers for your mapreduce jobs as per your data volume.
>>>
>>> Regards
>>> Bejoy KS
>>>
>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>
>>>> Hi, all
>>>>
>>>> I was wondering what's the default number of reducer if I don't set it
>>>> in configuration?
>>>>
>>>> Will it change dynamically according to the output volume of Mapper?
>>>>
>>>> --
>>>> YANG, Lin
>>>>
>>>>
>>>
>>
>>
>> --
>> YANG, Lin
>>
>>
>
Re: what's the default reducer number?
Posted by Jagat Singh <ja...@gmail.com>.
Just to add the name is depreciated in new Hadoop
Try to find
mapreduce.job.reduces
On Tue, Sep 11, 2012 at 9:43 PM, Bejoy Ks <be...@gmail.com> wrote:
> Hi Lin
>
> The default values for all the properties are in
> core-default.xml
> hdfs-default.xml and
> mapred-default.xml
>
>
> Regards
> Bejoy KS
>
>
> On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, Bejoy
>>
>> Thanks for you reply.
>>
>> where could I find the default value of mapred.reduce.tasks ? I have
>> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
>> found it.
>>
>>
>> 2012/9/11 Bejoy Ks <be...@gmail.com>
>>
>>> Hi Lin
>>>
>>> The default value for number of reducers is 1
>>>
>>> <name>mapred.reduce.tasks</name>
>>> <value>1</value>
>>>
>>> It is not determined by data volume. You need to specify the number of
>>> reducers for your mapreduce jobs as per your data volume.
>>>
>>> Regards
>>> Bejoy KS
>>>
>>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>>
>>>> Hi, all
>>>>
>>>> I was wondering what's the default number of reducer if I don't set it
>>>> in configuration?
>>>>
>>>> Will it change dynamically according to the output volume of Mapper?
>>>>
>>>> --
>>>> YANG, Lin
>>>>
>>>>
>>>
>>
>>
>> --
>> YANG, Lin
>>
>>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default values for all the properties are in
core-default.xml
hdfs-default.xml and
mapred-default.xml
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, Bejoy
>
> Thanks for you reply.
>
> where could I find the default value of mapred.reduce.tasks ? I have
> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
> found it.
>
>
> 2012/9/11 Bejoy Ks <be...@gmail.com>
>
>> Hi Lin
>>
>> The default value for number of reducers is 1
>>
>> <name>mapred.reduce.tasks</name>
>> <value>1</value>
>>
>> It is not determined by data volume. You need to specify the number of
>> reducers for your mapreduce jobs as per your data volume.
>>
>> Regards
>> Bejoy KS
>>
>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, all
>>>
>>> I was wondering what's the default number of reducer if I don't set it
>>> in configuration?
>>>
>>> Will it change dynamically according to the output volume of Mapper?
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default values for all the properties are in
core-default.xml
hdfs-default.xml and
mapred-default.xml
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, Bejoy
>
> Thanks for you reply.
>
> where could I find the default value of mapred.reduce.tasks ? I have
> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
> found it.
>
>
> 2012/9/11 Bejoy Ks <be...@gmail.com>
>
>> Hi Lin
>>
>> The default value for number of reducers is 1
>>
>> <name>mapred.reduce.tasks</name>
>> <value>1</value>
>>
>> It is not determined by data volume. You need to specify the number of
>> reducers for your mapreduce jobs as per your data volume.
>>
>> Regards
>> Bejoy KS
>>
>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, all
>>>
>>> I was wondering what's the default number of reducer if I don't set it
>>> in configuration?
>>>
>>> Will it change dynamically according to the output volume of Mapper?
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default values for all the properties are in
core-default.xml
hdfs-default.xml and
mapred-default.xml
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, Bejoy
>
> Thanks for you reply.
>
> where could I find the default value of mapred.reduce.tasks ? I have
> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
> found it.
>
>
> 2012/9/11 Bejoy Ks <be...@gmail.com>
>
>> Hi Lin
>>
>> The default value for number of reducers is 1
>>
>> <name>mapred.reduce.tasks</name>
>> <value>1</value>
>>
>> It is not determined by data volume. You need to specify the number of
>> reducers for your mapreduce jobs as per your data volume.
>>
>> Regards
>> Bejoy KS
>>
>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, all
>>>
>>> I was wondering what's the default number of reducer if I don't set it
>>> in configuration?
>>>
>>> Will it change dynamically according to the output volume of Mapper?
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default values for all the properties are in
core-default.xml
hdfs-default.xml and
mapred-default.xml
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 5:06 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, Bejoy
>
> Thanks for you reply.
>
> where could I find the default value of mapred.reduce.tasks ? I have
> checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
> found it.
>
>
> 2012/9/11 Bejoy Ks <be...@gmail.com>
>
>> Hi Lin
>>
>> The default value for number of reducers is 1
>>
>> <name>mapred.reduce.tasks</name>
>> <value>1</value>
>>
>> It is not determined by data volume. You need to specify the number of
>> reducers for your mapreduce jobs as per your data volume.
>>
>> Regards
>> Bejoy KS
>>
>> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>>
>>> Hi, all
>>>
>>> I was wondering what's the default number of reducer if I don't set it
>>> in configuration?
>>>
>>> Will it change dynamically according to the output volume of Mapper?
>>>
>>> --
>>> YANG, Lin
>>>
>>>
>>
>
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
Hi, Bejoy
Thanks for you reply.
where could I find the default value of mapred.reduce.tasks ? I have
checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
found it.
2012/9/11 Bejoy Ks <be...@gmail.com>
> Hi Lin
>
> The default value for number of reducers is 1
>
> <name>mapred.reduce.tasks</name>
> <value>1</value>
>
> It is not determined by data volume. You need to specify the number of
> reducers for your mapreduce jobs as per your data volume.
>
> Regards
> Bejoy KS
>
> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering what's the default number of reducer if I don't set it in
>> configuration?
>>
>> Will it change dynamically according to the output volume of Mapper?
>>
>> --
>> YANG, Lin
>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
Hi, Bejoy
Thanks for you reply.
where could I find the default value of mapred.reduce.tasks ? I have
checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
found it.
2012/9/11 Bejoy Ks <be...@gmail.com>
> Hi Lin
>
> The default value for number of reducers is 1
>
> <name>mapred.reduce.tasks</name>
> <value>1</value>
>
> It is not determined by data volume. You need to specify the number of
> reducers for your mapreduce jobs as per your data volume.
>
> Regards
> Bejoy KS
>
> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering what's the default number of reducer if I don't set it in
>> configuration?
>>
>> Will it change dynamically according to the output volume of Mapper?
>>
>> --
>> YANG, Lin
>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
Hi, Bejoy
Thanks for you reply.
where could I find the default value of mapred.reduce.tasks ? I have
checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
found it.
2012/9/11 Bejoy Ks <be...@gmail.com>
> Hi Lin
>
> The default value for number of reducers is 1
>
> <name>mapred.reduce.tasks</name>
> <value>1</value>
>
> It is not determined by data volume. You need to specify the number of
> reducers for your mapreduce jobs as per your data volume.
>
> Regards
> Bejoy KS
>
> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering what's the default number of reducer if I don't set it in
>> configuration?
>>
>> Will it change dynamically according to the output volume of Mapper?
>>
>> --
>> YANG, Lin
>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Jason Yang <li...@gmail.com>.
Hi, Bejoy
Thanks for you reply.
where could I find the default value of mapred.reduce.tasks ? I have
checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
found it.
2012/9/11 Bejoy Ks <be...@gmail.com>
> Hi Lin
>
> The default value for number of reducers is 1
>
> <name>mapred.reduce.tasks</name>
> <value>1</value>
>
> It is not determined by data volume. You need to specify the number of
> reducers for your mapreduce jobs as per your data volume.
>
> Regards
> Bejoy KS
>
> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering what's the default number of reducer if I don't set it in
>> configuration?
>>
>> Will it change dynamically according to the output volume of Mapper?
>>
>> --
>> YANG, Lin
>>
>>
>
--
YANG, Lin
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default value for number of reducers is 1
<name>mapred.reduce.tasks</name>
<value>1</value>
It is not determined by data volume. You need to specify the number of
reducers for your mapreduce jobs as per your data volume.
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, all
>
> I was wondering what's the default number of reducer if I don't set it in
> configuration?
>
> Will it change dynamically according to the output volume of Mapper?
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default value for number of reducers is 1
<name>mapred.reduce.tasks</name>
<value>1</value>
It is not determined by data volume. You need to specify the number of
reducers for your mapreduce jobs as per your data volume.
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, all
>
> I was wondering what's the default number of reducer if I don't set it in
> configuration?
>
> Will it change dynamically according to the output volume of Mapper?
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default value for number of reducers is 1
<name>mapred.reduce.tasks</name>
<value>1</value>
It is not determined by data volume. You need to specify the number of
reducers for your mapreduce jobs as per your data volume.
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, all
>
> I was wondering what's the default number of reducer if I don't set it in
> configuration?
>
> Will it change dynamically according to the output volume of Mapper?
>
> --
> YANG, Lin
>
>
Re: what's the default reducer number?
Posted by Bejoy Ks <be...@gmail.com>.
Hi Lin
The default value for number of reducers is 1
<name>mapred.reduce.tasks</name>
<value>1</value>
It is not determined by data volume. You need to specify the number of
reducers for your mapreduce jobs as per your data volume.
Regards
Bejoy KS
On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <li...@gmail.com>wrote:
> Hi, all
>
> I was wondering what's the default number of reducer if I don't set it in
> configuration?
>
> Will it change dynamically according to the output volume of Mapper?
>
> --
> YANG, Lin
>
>