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RE: Calling one MR job within another MR job
Hi Ravi,

There is no job dependency so I cannot use chaining MR or JobControl as you suggested.
I have 2 relatively big files, I start processing with File1 as input to MR1 job , now this processing required to find the data from File2. One way to do is loop through File2 and get the data. Other way to pass File2 in MR2 job for parallel processing.

Second option is making hinting me to call an MR2 job inside from MR1 job. I am sure this is the common problem that people usually face. What is the best way to resolve this  kind of issue.


From: Ravi teja ch n v [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, April 04, 2012 4:35 PM
Subject: RE: Calling one MR job within another MR job
Hi Stuti,

If you are looking for MRjob2 to run after MRjob1, ie the job dependency,

you can use JobControl API, where you can manage the dependencies.

Calling another Job from a Mapper is not a good idea.


Ravi Teja

From: Stuti Awasthi [[EMAIL PROTECTED]]
Sent: 04 April 2012 16:04:19
Subject: Calling one MR job within another MR job
Hi all,

We have a usecase in which I start with first MR1 job with input file as File1.txt, and from this job, call another MR2 job with input as File2.txt
So :


My queries are is this kind of approach is possible and how much are the implications from the performance perspective.
Stuti Awasthi
HCL Comnet Systems and Services Ltd
F-8/9 Basement, Sec-3,Noida.

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