distributed-system

I am creating a program to analyze PDF, DOC and DOCX files. These files are stored in HDFS. When I start my MapReduce job, I want the map function to have the Filename as key and the Binary Contents as value. I then want to create a stream reader which I can pass to the PDF parser library. How can I achieve that the key/value pair for the Map Phase is filename/filecontents? I am using Hadoop 0.20.2 This is older code that starts a job: public static void main(String[] args) throws Exception { JobConf conf = new JobConf(PdfReader.class); conf.setJobName("pdfreader"); conf.setOutputKeyClass(Text

After reading paxos and raft paper, I have following confusion: paxos paper only describe consensus on single log entry, which is equivalent the leader election part of the raft algorithm. What's the advantage of paxos's approach over the simple random timeout approach in raft's leader election? It is a common misconception that the original Paxos papers don't use a stable leader. In Paxos Made Simple on page 6 in the section entitled “The Implementation” Lamport wrote: The algorithm chooses a leader, which plays the roles of the distinguished proposer and the distinguished learner. This is