Does Giraph supports multi threaded MapJobs

[Zuhair Khayyat <zu...@kaust.edu.sa>]

Dear Giraph Community,

Since Giraph is a single Mapper job; does it support multi threaded Map
Jobs handlers? In other words, can a Giraph worker be a multi threaded
worker? If I am implementing my own aggregator, do I have to consider
thread safe operations?

Thank you,
Zuhair Khayyat

Re: Does Giraph supports multi threaded MapJobs

[André Kelpe <ef...@googlemail.com>]

Hi Zuhair,

giraph will spawn multiple mappers depending on how many you
configure. If you look into the ShortestPathExample
(https://cwiki.apache.org/confluence/display/GIRAPH/Shortest+Paths+Example),
you will see this piece of code, which controls the number of workers:

job.setWorkerConfiguration(Integer.parseInt(argArray[3]),
                               Integer.parseInt(argArray[3]),
                               100.0f);

It is also quite useful to read through the constants in the GiraphJob class.

HTH

-André


2012/5/23 Zuhair Khayyat <zu...@kaust.edu.sa>:
> Dear Giraph Community,
>
> Since Giraph is a single Mapper job; does it support multi threaded Map Jobs
> handlers? In other words, can a Giraph worker be a multi threaded worker? If
> I am implementing my own aggregator, do I have to consider thread safe
> operations?
>
> Thank you,
> Zuhair Khayyat