[vsipl++] [patch] Parallel Howto

[Mark Mitchell]

Jules Bergmann wrote:

> Please have a look and let me know what you think.

I'm excited to see this!  I think it's very important.  (Along with the
rest of the tutorial.)  As we're learning from the fellow at ARL, the
Georgia Tech User's Guide is actually worse than useless: it's examples
apparently don't work at all.

Overall, I think the structure of the tutorial, and of the chapter you
added, are good.  However, I think the words need a bit of work.  I also
think the SAR chapter should be integrated with the chapter you wrote,
or that they should go near each other, at least.

Here are a few nits:

1. Accepted practice is to use the second person for tutorials, user's
guides, etc.  So, "You will learn how to parallelize the serial
version", rather than "We will show how to ...".  (That applies in lots
of places.)  That also means that you can use the imperative case:
"Next, create data structures" instead of "Next, we need to create data
structures".

2. I've started saying "uni-processor" and "multi-processor" instead of
"serial" and "parallel".  What do you think about adopting that
convention?  The problem is that uniprocessors can be parallel (SIMD
units, or Cell).

3. In the section on Parallel Fast Convolution, it's not clear what the
point of the first paragraph is.  Are you explaining what "implicit
parallelism" is?  Or, suggesting that implicit parallelism is bad, and
that we want to use maps instead?  Or...?

4. In the section on Explicit Parallelism, drop the sentence "For
example, if our system had multiple channels, ..."  That sentence
suggests the VSIPL++ API is missing something (versions for tensors),
which sounds bad.  And, the next sentence gives a good motivation for
the rest of the section anyhow.

I'd like to take a whack at editing this on the plane to Orlando next
Monday.  So, please check it in at some point before that.

Thanks,

-- 
Mark Mitchell
CodeSourcery
mark at codesourcery.com
(650) 331-3385 x713