hadoop-common-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Leo Leung <lle...@ddn.com>
Subject RE: Question on MapReduce
Date Fri, 11 May 2012 19:58:00 GMT

This maybe dated materials.

Cloudera and HDP folks please correct with updates :)



Hope this helps.

-----Original Message-----
From: Satheesh Kumar [mailto:nkseam@gmail.com] 
Sent: Friday, May 11, 2012 12:48 PM
To: common-user@hadoop.apache.org
Subject: Re: Question on MapReduce

Thanks, Leo. What is the config of a typical data node in a Hadoop cluster
- cores, storage capacity, and connectivity (SATA?).? How many tasktrackers scheduled per
core in general?

Is there a best practices guide somewhere?


On Fri, May 11, 2012 at 10:48 AM, Leo Leung <lleung@ddn.com> wrote:

> Nope, you must tune the config on that specific super node to have 
> more M/R slots (this is for 1.0.x) This does not mean the JobTracker 
> will be eager to stuff that super node with all the M/R jobs at hand.
> It still goes through the scheduler,  Capacity Scheduler is most 
> likely what you have.  (check your config)
> IMO, If the data locality is not going to be there, your cluster is 
> going to suffer from Network I/O.
> -----Original Message-----
> From: Satheesh Kumar [mailto:nkseam@gmail.com]
> Sent: Friday, May 11, 2012 9:51 AM
> To: common-user@hadoop.apache.org
> Subject: Question on MapReduce
> Hi,
> I am a newbie on Hadoop and have a quick question on optimal compute vs.
> storage resources for MapReduce.
> If I have a multiprocessor node with 4 processors, will Hadoop 
> schedule higher number of Map or Reduce tasks on the system than on a 
> uni-processor system? In other words, does Hadoop detect denser 
> systems and schedule denser tasks on multiprocessor systems?
> If yes, will that imply that it makes sense to attach higher capacity 
> storage to store more number of blocks on systems with dense compute?
> Any insights will be very useful.
> Thanks,
> Satheesh

View raw message