Abhishek: It may not be entirely accurate as it incorporates additional actions in the time, but simply looking at the task run time for local tasks vs. non-local tasks should give you a rough estimate. Task locality can be determined via the JT web UI as can task run times.
Hope this helps. On Sat, Apr 3, 2010 at 8:11 PM, abhishek sharma <[email protected]> wrote: > Hi all, > > I wanted to measure the time it takes to read input split for a map > task. For my cluster, I am interested in measuring the overhead of > fetching the input to a map task over the network as opposed to > reading from the local disk. > > Is there an easy way to instrument some function to log this > information (say, in the TaskTracker logs)? > > Thanks, > Abhishek > -- Eric Sammer phone: +1-917-287-2675 twitter: esammer data: www.cloudera.com
