Look on the job tracker web UI is parameter has taken effect (port 50030)

It might be in the wrong config file or something
Serge

From: Mark Kerzner <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Reply-To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Date: Tuesday, November 13, 2012 5:19 PM
To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Subject: Re: mapred.tasktracker.map.tasks.maximum

1.0.1

On Tue, Nov 13, 2012 at 10:18 AM, Serge Blazhiyevskyy <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>> wrote:
What hadoop version are we talking about?

From: Mark Kerzner <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]><mailto:[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>>
Reply-To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]><mailto:[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]><mailto:[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>>
Date: Tuesday, November 13, 2012 5:16 PM
To: Hadoop User <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]><mailto:[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>>
Subject: mapred.tasktracker.map.tasks.maximum

Hi,

I have a cluster with 4 nodes and 32 many cores on each. My default value for the maximum number of mappers per slot is 1:

  <property>
    <name>mapred.tasktracker.map.tasks.maximum</name>
    <!-- see other kb entry about this one. -->
    <value>1</value>
    <final>true</final>
  </property>
(which I think is wrong).

Howeve, when sizable jobs run, I see 65 mappers working, so it seems that it does create more than 1 mapper per node.

Questions: what maximum number of mappers would be appropriate in this situation? Is that the right way to set them?

Thank you. Sincerely,
Mark

What hadoop version are we talking about?

From: Mark Kerzner <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Reply-To: "[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>" <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Date: Tuesday, November 13, 2012 5:16 PM
To: Hadoop User <[EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]>>
Subject: mapred.tasktracker.map.tasks.maximum

Hi,

I have a cluster with 4 nodes and 32 many cores on each. My default value for the maximum number of mappers per slot is 1:

  <property>
    <name>mapred.tasktracker.map.tasks.maximum</name>
    <!-- see other kb entry about this one. -->
    <value>1</value>
    <final>true</final>
  </property>
(which I think is wrong).

Howeve, when sizable jobs run, I see 65 mappers working, so it seems that it does create more than 1 mapper per node.

Questions: what maximum number of mappers would be appropriate in this situation? Is that the right way to set them?

Thank you. Sincerely,
Mark