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Re: Re: Questions About Passing Parameters to Hadoop Job
Though it is recommended for large files, DistributedCache might be a good
alternative for you.

Karthik Kambatla
2009/11/22 Gang Luo <[EMAIL PROTECTED]>

> So, you want to read the sample file in main and add each line to job by
> job.set, and then read these lines in mapper by job.get?
> I think it is better to name the data file as input source to mapper, while
> read the whole sample file in each mapper instance using HDFS api, and then
> compare them. It is actually how map-side join works.
> Gang Luo
> ---------
> Department of Computer Science
> Duke University
> (919)316-0993
> ----- 原始邮件 ----
> 发件人: Boyu Zhang <[EMAIL PROTECTED]>
> 发送日期: 2009/11/22 (周日) 3:21:23 下午
> 主   题: Questions About Passing Parameters to Hadoop Job
> Dear All,
> I am implementing an algorithm that read a data file(.txt file,
> approximately 90MB), compare each line of the data file with each line of a
> specific samples file(.txt file, approximately 20MB). To do this, I need to
> pass each line of the samples file as parameters to map-reduce job. And
> they
> are large, in a sense.
> My current way is that I use the job.set and job.get to set and retrieve
> these lines as configurations. But it is not efficient at all!
> Could anyone help me with an alternative solution? Thanks a million!
> Boyu Zhang
> University of Delaware
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