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Re: can't disable speculative execution?
Thanks Harsh

I see

then there seems to be some small problems with the Splitter / InputFormat.

I'm just reading a 1-line text file through pig:

A = LOAD 'myinput.txt' ;

supposedly it should generate at most 1 mapper.

but in reality , it seems that pig generated 3 mappers, and basically fed
empty input to 2 of the mappers
Thanks
Yang

On Wed, Jul 11, 2012 at 10:00 PM, Harsh J <[EMAIL PROTECTED]> wrote:

> Yang,
>
> No, those three are individual task attempts.
>
> This is how you may generally dissect an attempt ID when reading it:
>
> attempt_201207111710_0024_m_000000_0
>
> 1. "attempt" - indicates its an attempt ID you'll be reading
> 2. "201207111710" - The job tracker timestamp ID, indicating which
> instance of JT ran this job
> 3. "0024" - The Job ID for which this was a task attempt
> 4. "m" - Indicating this is a mapper (reducers are "r")
> 5. "000000" - The task ID of the mapper (00000 is the first mapper,
> 00001 is the second, etc.)
> 6. "0" - The attempt # for the task ID. 0 means it is the first
> attempt, 1 indicates the second attempt, etc.
>
> On Thu, Jul 12, 2012 at 9:16 AM, Yang <[EMAIL PROTECTED]> wrote:
> > I set the following params to be false in my pig script (0.10.0)
> >
> > SET mapred.map.tasks.speculative.execution false;
> > SET mapred.reduce.tasks.speculative.execution false;
> >
> >
> > I also verified in the jobtracker UI in the job.xml that they are indeed
> > set correctly.
> >
> > when the job finished, jobtracker UI shows that there is only one attempt
> > for each task (in fact I have only 1 task too).
> >
> > but when I went to the tasktracker node, looked under the
> > /var/log/hadoop/userlogs/job_id_here/
> > dir , there are 3 attempts dir ,
> >  job_201207111710_0024 # ls
> > attempt_201207111710_0024_m_000000_0
>  attempt_201207111710_0024_m_000001_0
> >  attempt_201207111710_0024_m_000002_0  job-acls.xml
> >
> > so 3 attempts were indeed fired ??
> >
> > I have to get this controlled correctly because I'm trying to debug the
> > mappers through eclipse,
> > but if more than 1 mapper process is fired, they all try to connect to
> the
> > same debugger port, and the end result is that nobody is able to
> > hook to the debugger.
> >
> >
> > Thanks
> > Yang
>
>
>
> --
> Harsh J
>