Re: [boost] [Review][MPI] sending large arrays

From: Matthias Troyer (troyer_at_[hidden])
Date: 2006-09-07 16:57:36

On Sep 7, 2006, at 9:52 PM, Geoffrey Irving wrote:

> Oops.  I found the new array optimizations in serialization CVS.
> It might be worth adding a note in the MPI documentation to this  
> effect,
> especially since the current serialization documentation says that
> serializing an array translates directly into a for loop outside of
> the archive classes.
>
> Would it be straightforward to extend the array optimizations to  
> handle
> run-time strided arrays (which are necessary to send slices of
> multidimensional arrays)?  If simple array support required modifying
> (improving) serialization, would strides require it as well?

It will not require modifications of the serialization library if
  - if you just want to optimize a specific data structure of which  
you can control the serialization
  - and if you just want it for one particular archive

The reason why we modified serialization, introducing the array  
wrapper was because
  - several archive types could optimize for unit stride arrays
  - the serialization function of a number of classes could profit

With the exception of modifying the serialization of builtin arrays,  
the archives did not have to be touched. Thus, extending array  
wrapper to non unit stride arrays would be straightforward and, as  
far as I can see now, not require a change to the serialization library.

Matthias