From 0bae506c221f9736d08a6fba00ce5a862ab43cce Mon Sep 17 00:00:00 2001 From: Akira Ajisaka Date: Fri, 22 Jan 2016 21:08:31 +0900 Subject: [PATCH] HADOOP-12730. Hadoop streaming -mapper and -reducer options are wrongly documented as required. Contributed by Kengo Seki. --- hadoop-common-project/hadoop-common/CHANGES.txt | 3 +++ .../hadoop-streaming/src/site/markdown/HadoopStreaming.md.vm | 4 ++-- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt index 2fb1173e87..36cac2f3fb 100644 --- a/hadoop-common-project/hadoop-common/CHANGES.txt +++ b/hadoop-common-project/hadoop-common/CHANGES.txt @@ -1642,6 +1642,9 @@ Release 2.8.0 - UNRELEASED HADOOP-12659. Incorrect usage of config parameters in token manager of KMS. (Mingliang Liu via xyao) + HADOOP-12730. Hadoop streaming -mapper and -reducer options are wrongly + documented as required. (Kengo Seki via aajisaka) + Release 2.7.3 - UNRELEASED INCOMPATIBLE CHANGES diff --git a/hadoop-tools/hadoop-streaming/src/site/markdown/HadoopStreaming.md.vm b/hadoop-tools/hadoop-streaming/src/site/markdown/HadoopStreaming.md.vm index 0598a35ed6..222335296b 100644 --- a/hadoop-tools/hadoop-streaming/src/site/markdown/HadoopStreaming.md.vm +++ b/hadoop-tools/hadoop-streaming/src/site/markdown/HadoopStreaming.md.vm @@ -96,8 +96,8 @@ The Hadoop streaming command options are listed here: |:---- |:---- |:---- | | -input directoryname or filename | Required | Input location for mapper | | -output directoryname | Required | Output location for reducer | -| -mapper executable or JavaClassName | Required | Mapper executable | -| -reducer executable or JavaClassName | Required | Reducer executable | +| -mapper executable or JavaClassName | Optional | Mapper executable. If not specified, IdentityMapper is used as the default | +| -reducer executable or JavaClassName | Optional | Reducer executable. If not specified, IdentityReducer is used as the default | | -file filename | Optional | Make the mapper, reducer, or combiner executable available locally on the compute nodes | | -inputformat JavaClassName | Optional | Class you supply should return key/value pairs of Text class. If not specified, TextInputFormat is used as the default | | -outputformat JavaClassName | Optional | Class you supply should take key/value pairs of Text class. If not specified, TextOutputformat is used as the default |