Thomas, So, will BSPPeer.getAllPeerNames() will return all the task locations instead of the groom locations?
Thanks, Praveen On Fri, Mar 23, 2012 at 4:31 PM, Thomas Jungblut < [email protected]> wrote: > Hey, > > 1: Each task has its own RPC Server, so you directly send to a task, rather > than to a groom. > 2: BSPMessageBundle is a bundle of messages that are batched per > destination to improve the transfer speed. Combiners are there to do the > same purpose, so you return a "message-batch" when combining. > 3: Hadoop is input-driven. That's from the functional programming where you > have an input list and apply functions like map and reduce on it. > BSP is not strongly functional related and we had no input before. For > several task no input is a valid input, e.G. realtime processing. However > you want to control the parallelization factor by controlling how many > tasks are launched. > So it is a mixture of backward compatibility and freedom of launching a few > tasks in a cluster without input. > > Regarding your other mail, if you want to contribute parts of a mapreduce > version, feel free to code one. I have not scheduled it to any release > since this is just a "side-effect" example. > > Hope I clarified it :) > Thanks! > > Am 23. März 2012 11:47 schrieb Praveen Sripati <[email protected]>: > > > Hi, > > > > 1. 0.4.0 introduced multiple tasks on groom servers. How does the > framework > > send a message to a particular task on a groom server. If I am not wrong, > > BSPPeer.send() sends messages to all the tasks on a groom server and it > is > > an overhead. > > > > 2. What is the difference between message combiners (0.4.0) and > > BSPMessageBundle (0.3.0)? > > > > 3. What is the significance of BSPJob.setNumBspTask()? I thought that in > > Hama the input will be split and a task will be spawned for each split in > > the groom server similar to Hadoop? > > > > Regards, > > Praveen > > > > > > -- > Thomas Jungblut > Berlin <[email protected]> >
