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Posted to common-commits@hadoop.apache.org by om...@apache.org on 2011/03/04 05:05:12 UTC
svn commit: r1077340 -
/hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml
Author: omalley
Date: Fri Mar 4 04:05:12 2011
New Revision: 1077340
URL: http://svn.apache.org/viewvc?rev=1077340&view=rev
Log:
commit dcb9796642320efb72df3817eba3625e778f23b4
Author: Hemanth Yamijala <yh...@yahoo-inc.com>
Date: Fri Mar 19 13:26:36 2010 +0530
MAPREDUCE:1417 from https://issues.apache.org/jira/secure/attachment/12439247/MAPREDUCE-1417-20.patch
+++ b/YAHOO-CHANGES.txt
+ MAPREDUCE-1417. Update forrest documentation for private
+ and public distributed cache files. (Ravi Gummadi via yhemanth)
+
Modified:
hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml
Modified: hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml?rev=1077340&r1=1077339&r2=1077340&view=diff
==============================================================================
--- hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml (original)
+++ hadoop/common/branches/branch-0.20-security-patches/src/docs/src/documentation/content/xdocs/mapred_tutorial.xml Fri Mar 4 04:05:12 2011
@@ -1914,7 +1914,36 @@
<code>mapred.job.classpath.{files|archives}</code>. Similarly the
cached files that are symlinked into the working directory of the
task can be used to distribute native libraries and load them.</p>
-
+ <section>
+ <title>Private and Public DistributedCache Files</title>
+ <p>DistributedCache files can be private or public, that
+ determines how they can be shared on the slave nodes.</p>
+ <ul>
+ <li>"Private" DistributedCache files are cached in a local
+ directory private to the user whose jobs need these
+ files. These files are shared by all
+ tasks and jobs of the specific user only and cannot be accessed by
+ jobs of other users on the slaves. A DistributedCache file becomes private by
+ virtue of its permissions on the file system where the files
+ are uploaded, typically HDFS. If the file has no world readable
+ access, or if the directory path leading to the file has no
+ world executable access for lookup, then the file becomes private.
+ </li>
+ <li>"Public" DistributedCache files are cached in a global
+ directory and the file access is setup such that they are
+ publicly visible to all users. These files can be shared by
+ tasks and jobs of all users on the slaves.
+ A DistributedCache file becomes public by virtue of its permissions
+ on the file system where the files are uploaded, typically HDFS.
+ If the file has world readable access, AND if the directory
+ path leading to the file has world executable access for lookup,
+ then the file becomes public. In other words, if the user intends
+ to make a file publicly available to all users, the file permissions
+ must be set to be world readable, and the directory permissions
+ on the path leading to the file must be world executable.
+ </li>
+ </ul>
+ </section>
</section>
<section>