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Subject: Re: [OMPI devel] New MOSIX components draft
From: Alex Margolin (alex.margolin_at_[hidden])
Date: 2012-03-31 19:28:50

I've added some documentation and made a few other changes in the hope
of making the code more readable (the attached diff replaces the
previous one), though the BTL is still giving me that error. There are
some TODOs in the code where I was unsure about the code (it should
still work - I'm not aware of any code missing), and I'll appreciate any

Here's an example: Suppose I have a TCP and a UDP channel in parallel.
This is not critical for the first version (I'm not using UDP before I
make TCP work), but I an curious as to how I can make the upper layers
make use of both according to the task at hand. It would seem that TCP
requires less code overhead, but requires more resources then UDP, but I
ran a few tests and it seems TCP can beat UDP in performance is some
scenarios... It sounds odd to me, but this may be the result of
intensive kernel optimizations on the TCP side. Still, UDP may perform
better with fire-and-forget scenarios.

Thanks a lot (and sorry for the hassle),

On 03/31/2012 07:04 PM, Alex Margolin wrote:
> Hi,
> I think i'm close to finishing an initial version of the MOSIX support
> for open-mpi. A perliminary draft is attached.
> The support consists of two modules: ODLS module for launching
> processes under MOSIX, and BTL module for efficient communication
> between processes.
> I'm not quite there yet - I'm sure the BTL module needs more work...
> first because it fails (see error output below) and second because I'm
> not sure I got all the function output right. I've written some
> documentation inside the code, which is pretty short at the moment.
> The ODLS component is working fine.