Thank you very much, Piyush! :) May I know more about how to use "traces"?
And -- yes, please teach me if possible, experts! :) Thanks a lot, -Rita :)) On Sat, Aug 14, 2010 at 9:42 PM, Piyush Garg <[email protected]> wrote: > Hi Rita, > > I have just started to learn hadoop as well, I know there is a long way > to go. > I found some useful links which I am sharing with you. > > Hadoop Tutorial - YDN > <http://developer.yahoo.com/hadoop/tutorial/index.html> excellent > beginners tutorial and well organized. > Running Hadoop On Ubuntu Linux (Single-Node Cluster) - Michael G. Noll > < > http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Single-Node_Cluster%29 > > > Running_Hadoop_On_Ubuntu_Linux_(Multi-Node_Cluster) > < > http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Multi-Node_Cluster%29 > > > The tutorial on the hadoop wiki > <http://hadoop.apache.org/common/docs/r0.20.0/mapred_tutorial.html> is > too much for a beginner. > > Debugger: > I do not think you can easily do debugging using remote debugger. This > is natural since hadoop is not sequential programming, it would be very > difficult to debug its apps. > The only way to debug is to use traces. > > I think you can learn how to setup multi-node cluster, but for practice > session you can use single node setup. > > Lets see what the experts say. > > Thanks and Regards > Piyush Garg > > > On Sunday 15 August 2010 09:07 AM, Rita Liu wrote: > > Hi! > > > > I am a total beginner, but I am very interested in hadoop. I've already > > downloaded hadoop 0.19.2 and run on Ubuntu in single-node mode. Now I > want > > to do two things: > > > > 1. Explore how hadoop works internally with one of the example > applications > > hadoop provides > > 2. Write an application on my own > > > > Those two things bring me following questions: > > > > a. debugger? > > I am stuck since I don't know how to "explore" hadoop. I used to trace > > through the code using a debugger, but in this case, I don't know if > there > > is a good debugger to use; or -- maybe a debugger is not necessary for > > hadoop? If not, then how do you trace through the code to either debug or > > just gain an understanding about the system? May I know what you, > > experienced experts, do? :) > > > > b. Where to run hadoop? > > Also -- may I know where you run your hadoop? Do you run on linux, or on > VM > > -- in particular, Cloudera? I heard that Cloudera is good for writing > > mapreduce applications with hadoop itself as a blackbox; is it true? If > my > > ultimate goal is to understand how hadoop works internally, would it be > > better if I directly run it on linux? > > > > c. Single-node or multi-node? > > In the beginning (just like my case :p) would it be better to use > > single-node or multi-node? If the latter is true, should I obtain more > > machines, or should I use more virtual machines to create more nodes? > > > > As a newbie, I am sorry for all those basic (and silly, I know :$) > > questions. If possible, please help me out? Any suggestion or advice will > be > > greatly appreciated. Thank you very much! > > > > Best, > > Rita :) > > > > P.S. If my questions are not suitable for this mailing-list, please let > me > > apologize, and then, could you please direct me to other mailing-lists? > > Sorry, and thanks a lot! :) > > > > >
