[HADOOP-4041] IsolationRunner does not work as documented

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.18.0
• Fix Version/s: 0.21.0
• Component/s: documentation
• Hadoop Flags: Reviewed
• Release Note: Fixed a bug in IsolationRunner to make it work for map tasks.
• Assignee: Philip Martin
• Reporter: Yuri Pradkin
• Created: 28/Aug/08 16:17
• Updated: 24/Aug/10 20:34
• Resolved: 16/Jun/09 01:18

Description

IsolationRunner does not work as documented in the tutorial.

The tutorial says "To use the IsolationRunner, first set keep.failed.tasks.files to true (also see keep.tasks.files.pattern)."

Should be:
keep.failed.task.files (not tasks)

After the above was set (quoted from my message on hadoop-core):
> After the task
> hung, I failed it via the web interface. Then I went to the node that was
> running this task
>
> $ cd ...local/taskTracker/jobcache/job_200808071645_0001/work
> (this path is already different from the tutorial's)
>
> $ hadoop org.apache.hadoop.mapred.IsolationRunner ../job.xml
> Exception in thread "main" java.lang.NullPointerException
> at
> org.apache.hadoop.mapred.IsolationRunner.main(IsolationRunner.java:164)
>
> Looking at IsolationRunner code, I see this:
>
> 164 File workDirName = new File(lDirAlloc.getLocalPathToRead(
> 165 TaskTracker.getJobCacheSubdir()
> 166 + Path.SEPARATOR + taskId.getJobID()
> 167 + Path.SEPARATOR + taskId
> 168 + Path.SEPARATOR + "work",
> 169 conf). toString());
>
> I.e. it assumes there is supposed to be a taskID subdirectory under the job
> dir, but:
> $ pwd
> ...mapred/local/taskTracker/jobcache/job_200808071645_0001
> $ ls
> jars job.xml work
>
> – it's not there.

Issue Links

• is related to: MAPREDUCE-234 Isolation runner needs a testcase
• relates to: MAPREDUCE-1325 Fix IsolationRunner to run with reduces too