This is a version of code that runs on Facebook's data warehouse clusters and 
is powered by Apache Hadoop.  The size of the biggest single cluster is 30 PB 
and has 3000 nodes.

This code is based on Apache Hadoop 0.20.

FB-CHANGES.txt contains the additional pathches that have been committed to
the original code base.

PLEASE NOTE: 
 
 * This distribution includes cryptographic software that 
   is subject to U.S. export control laws and applicable 
   export and import laws of other countries. BEFORE using 
   any software made available from this site, it is your 
   responsibility to understand and comply with these laws. 
   This software is being exported in accordance with the 
   Export Administration Regulations. As of June 2009, you 
   are prohibited from exporting and re-exporting this 
   software to Cuba, Iran, North Korea, Sudan, Syria and 
   any other countries specified by regulatory update to 
   the U.S. export control laws and regulations. Diversion 
   contrary to U.S. law is prohibited.