<div dir="ltr">When you say "wireless node" - I assume you are referring to a distributed set of machines (a grid).<div><br></div><div>There are two scenarios to consider here:</div><div>(1) Building the subproblems (and handling their associated data) distributed, and</div><div>(2) Solving the subproblems in a distributed fashion.</div><div><br></div><div>For scenario (2), I have done just this in my commercial product life (at SAS) here: </div><div><a href="http://documentation.sas.com/?docsetId=ormpug&docsetVersion=14.2&docsetTarget=ormpug_decomp_toc.htm&locale=en">http://documentation.sas.com/?docsetId=ormpug&docsetVersion=14.2&docsetTarget=ormpug_decomp_toc.htm&locale=en</a></div><div><br></div><div>One thing, that might be obvious is that the potential speed-up is greatly burdened by the balance in the difficulty of solving the subproblems. This gets a little bit easier if you are willing to deal with non-determinism. But, in a deterministic framework (which is important for commercial applications), I have found that this paradigm really only works for special cases. The more generic approach often has one or two subproblems that dominate the pricing mechanism and very good parallel speedup is difficult to attain. That being said, it does help quite a bit on some instances. I think this is a wide open research area for understanding ways to improve this balance in such an environment by being more clever about how aggressive you really need to be on the subproblem resolution. I welcome any and all contributions to this study.</div><div><br></div><div>As for DIP, yes - there is no reason at all that the same paradigm (scenario (2)) would not work. The framework is setup for it. You would just need someone to work on it. I unfortunately don't have the cycles for much open source development these days. Ted Ralphs is the lead on DIP now and may have already thought about this. I'd be happy to consult (as time permits).</div><div><br></div><div>Now - scenario (1) is a different beast all together. On the surface, my answer would be that "no" - DIP is not really designed for that kind of implementation. Some of the more specific implementation details assume that the entire compact formulation (including the subproblems) are in memory on one machine. This assumptions simplifies quite a bit of the code workflow. But this is strictly a design issue. There is no algorithmic necessity for such a thing and I am sure with some work that DIP could be made to work this way. But, the original design that I worked out did not have this scenario in mind. I think the other COIN product, BCP did, in fact, have this concept in mind when it was designed. So - that might also be worth some investigation.</div><div><br></div><div>The other complexity that arises with scenario (1) is assuming that you wish to use a modeling language to interface with DIP. In that case, the modeling language itself would need to be able to handle distributed data and model building on a grid. </div><div><br></div><div>Scenario (1) is something that is on my long-term plan for my commercial work at SAS. But, is currently fairly low priority.</div><div><br></div><div>Cheers,</div><div>Matthew Galati</div><div><br></div><div><div><br></div></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Jan 16, 2017 at 6:35 PM, Stan Stringfellow <span dir="ltr"><<a href="mailto:stan.stringfellow@plasticfog.com" target="_blank">stan.stringfellow@plasticfog.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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Hi!</p>
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Can someone answer the following?</p>
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<li style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">
Is it possible to use DIP to deploy DW subproblem instances to separate wireless nodes? </li><li>If not, would it be possible to extend the code to handle this deployment scenario? Would that be extremely difficult to do? </li><li>Does it make sense to deploy a s<span style="font-family:Calibri,Arial,Helvetica,sans-serif">olution in this way? ...the motivation being that the subproblems could be solved directly on the wireless nodes without uploading large amounts of subproblem data
that originates on those nodes to the network core.</span><br>
</li></ul>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">I greatly appreciate it!</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">Stan Stringfellow</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br>
</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:8pt">CEO/Founder PlasticFog Group</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:8pt">San Diego, California</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:8pt">Email: stan.stringfellow@PlasticFog.<wbr>com</span></p>
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<span style="font-family:Calibri,Arial,Helvetica,sans-serif;font-size:8pt">Cell: <a href="tel:(858)%20349-7907" value="+18583497907" target="_blank">858-349-7907</a></span></p>
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