rocksdb

History

Dhruba Borthakur 9e84834eb4 Allow a configurable number of background threads. Summary: The background threads are necessary for compaction. For slower storage, it might be necessary to have more than one compaction thread per DB. This patch allows creating a configurable number of worker threads. The default reamins at 1 (to maintain backward compatibility). Test Plan: run all unit tests. changes to db-bench coming in a separate patch. Reviewers: heyongqiang Reviewed By: heyongqiang CC: MarkCallaghan Differential Revision: https://reviews.facebook.net/D5559		2012-09-19 15:51:08 -07:00
..
env_hdfs.h	Allow a configurable number of background threads.	2012-09-19 15:51:08 -07:00
hdfs.h	Make Leveldb save data into HDFS files. You have to set USE_HDFS in your environment variable to compile leveldb with HDFS support.	2012-06-14 00:29:01 -07:00
libhdfs.a	Add libhdfs.a to the build process.	2012-08-29 15:21:56 -07:00
README	Create leveldb server via Thrift.	2012-07-07 09:42:39 -07:00

README

This directory contains the hdfs extensions needed to make leveldb store
files in HDFS.

The hdfs.h file is copied from the Apache Hadoop 1.0 source code. 
It defines the libhdfs library
(http://hadoop.apache.org/common/docs/r0.20.2/libhdfs.html) to access 
data in HDFS.  The libhdfs.a is copied from the Apache Hadoop 1.0 build. 
It implements the API defined in hdfs.h. If your hadoop cluster is running
a different hadoop release, then install these two files manually from your
hadoop distribution and then recompile leveldb.

The env_hdfs.h file defines the leveldb objects that are needed to talk to an
underlying filesystem. 

If you want to compile leveldb with hdfs support, please set the following
enviroment variables appropriately:
   USE_HDFS=1
   JAVA_HOME=/usr/local/jdk-6u22-64
   LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/jdk-6u22-64/jre/lib/amd64/server:/usr/local/jdk-6u22-64/jre/lib/amd64/:./snappy/libs
   make clean all db_bench

To run dbbench,
  set CLASSPATH to include your hadoop distribution
  db_bench --hdfs="hdfs://hbaseudbperf001.snc1.facebook.com:9000"