hadoop-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Michel Segel <michael_se...@hotmail.com>
Subject Re: What is the preferred way to pass a small number of configuration parameters to a mapper or reducer
Date Fri, 28 Dec 2012 22:19:39 GMT
Sounds like someone is cheating on a test...

Sent from a remote device. Please excuse any typos...

Mike Segel

On Dec 28, 2012, at 3:10 PM, Ted Dunning <tdunning@maprtech.com> wrote:

> Answer B sounds pathologically bad to me.
> 
> A or C are the only viable options.
> 
> Neither B nor D work.  B fails because it would be extremely hard to get the right records
to the right components and because it pollutes data input with configuration data.  D fails
because statics don't work in parallel programs.
> 
> 
> On Fri, Dec 28, 2012 at 12:17 AM, Kshiva Kps <kshivakps@gmail.com> wrote:
>> 
>> Which one is current ..
>> 
>> What is the preferred way to pass a small number of configuration parameters to a
mapper or reducer?
>>  
>>  
>> A.  As key-value pairs in the jobconf object.
>>  
>> B.  As a custom input key-value pair passed to each mapper or reducer.
>>  
>> C.  Using a plain text file via the Distributedcache, which each mapper or reducer
reads.
>>  
>> D.  Through a static variable in the MapReduce driver class (i.e., the class that
submits the MapReduce job).
>>  
>> Answer: B
> 

Mime
View raw message