Hi,
I am getting the below error when I was using some one's code where they
are using hadoop-17 and have the method FileInputFormat.setInputPaths for
setting input paths for the job. The exact error is given below.
java.lang.NoSuchMethodError:
org.apache.hadoop.mapred.FileInputFormat.setInputP
The maximum number of files in HDFS depends on the amount of memory
available for the namenode. Each file object and each block object
takes about 150 bytes of the memory. Thus, if you have 1million files
and each file has 1 one block each, then you would need about 3GB of
memory for the namenode.
In hadoopstreaming, we accept input from stdin. If we want to compute the
document frequncy of words, the somplest way is to output words as keys and
file name as values. then how can we get the input file name passed to this
MapReduce job? Thanks.
--
Best Wishes
Meng Xinfan（蒙新泛）
Institute of Com
Dear all,
I am a newbie started using Haddop yesterday.
I am having WIndows XP, and following is the output of grep program, which I
had exceuted exactly after following instructions in QuickStart guide:-
$ bin/hadoop jar hadoop-0.17.0-examples.jar grp input output 'dfs[a-z.]+'
cygpath: cannot
Is there some statistics available to monitor which percentage of the
pairs remains in memory, and which percentage was written to disk?
Or which are these exceptional cases that you mention?
Hadoop goes to some lengths to make sure that things can stay in
memory as
much as possible. Ther
The in memory optimized Hadoop implementation sounds like it would be useful
for a realtime scalable subscription system. The example I'm interested in
testing is using Lucene MemoryIndex to execute millions of queries for
notification of clients. Where the Hadoop map is a serialized MemoryIndex
Rack Awareness
Typically large Hadoop clusters are arranged in *racks* and network traffic
between different nodes with in the same rack is much more desirable than
network traffic across the racks. In addition Namenode tries to place
replicas of block on multiple racks for improved fault toleranc
Hi Iver,
The implementation of the script depends on your setup. The main thing is
that it should be able to accept a bunch of IP addresses and DNS names and
be able to give back the rackIDs for each. It is a one-to-one correspondence
between what you pass and what you get back. For getting the rac
