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Hadoop >> mail # user >> can't disable speculative execution?

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Re: can't disable speculative execution?
Your problem is more from the fact that you are running > 1 map slot
per TT, and multiple mappers are getting run at the same time, all
trying to bind to the same port. Limit your TT's max map tasks to 1
when you're relying on such techniques to debug, or use the
LocalJobRunner/Apache MRUnit instead.

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