hi kubes: thank you for your answers! i'm sorry that i didn't express my question. i run nutch only on one machine! and ,i cann't debug hadoop in nutch.because the hadoop's exist is lib. how can i debug hadoop source in nutch?
and to my surprise ,the Tutorial "RunNutchInEclipse1.0" doesn't start and configure hadoop ,include master listen port etc. when i debug nutch through breakpoint, it display:"there is no source file attached to the class file URLClassPath.class!" why? can hadoop run in vmware machine? and i also met other problers ,it is in another message " run nutch on eclipse problem? "' thanks !!! Dennis Kubes-2 wrote: > > > > askNutch wrote: >> hi Kubes: >> You are the expert! >> >> Can you tell me What is the develop environment do you use to >> develop nutch ? > > Linux, Ubuntu (usually the most recent), sun jdk, core2 laptop (although > hoping to upgrade to a sagernotebook.com quad core soon :) ), Eclipse > stable (3.4 I think). >> >> such as IDE etc. >> >> I want to debug nutch. > > Debugging MapReduce, hence Nutch, jobs is difficult. The main reason > why is because Hadoop/Nutch spin up a new JVM for each Map and Reduce > job so it is difficult to connect to that JVM as it is created and > launched automagically. Here are some options depending on what you are > trying to debug: > > 1) Run all hadoop servers processes (namenode, etc.) through eclipse > using the internal debugger. This isn't always the best way, usually > only used when debugging some part of the hadoop infrastructure such as > socket communication. > > 2) Run most of the hadoop servers in separate processes, run the > tasktracker inside of eclipse with the internal debugger. This is > mainly used when debugging a specific MapRunner, MapTask, or ReduceTask > interacting with Hadoop. You won't be able to debug the Map or Reduce > task itself, just the communication with the Hadoop server, for instance > reporting status. > > 3) Debugging the Map/Reduce task itself. Logging. Judicious logging is > most often what I use. Also do very small example if you can help it to > give yourself small turnaround times. Unless your problem is occurring > only on a large dataset, don't debug on a large data set. > > Hope this helps. > > Dennis > >> >> thank you !!! > > -- View this message in context: http://www.nabble.com/hi-%3Athe-question-about-develop-environment%21-tp23170026p23191120.html Sent from the Nutch - User mailing list archive at Nabble.com.
