[Os-project-managers] Fork in the Road

[Horand Gassmann]

Kipp Martin <kmartin at chicagobooth.edu> wrote:

> Hi Gus:
>
>>
>> Let me add another thought. This whole discussion has been extremely
>> stimulating, and it has made me realize that there is a fundamental
>> difference between input and output methods as far as encapsulation is
>> concerned. We do not have the same problem with the OSoL format, because
>> we can always pass the entire OSoL file down the line. The server reads
>> its pieces, but it does not have to "decapsulate" the parts that need to
>> go to the server. You pay the price of a bit of redundancy, because what
>> the server passes to the solver has information we know to be useless,
>> but that is trivial. It's the return path that is hard.
>
> Aha! You say:  "You pay the price of a bit of redundancy, because what
> the server passes to the solver has information we know to be useless,
> but that is trivial."
>
> Then solver writers need to know what is useless, i.e. what they  
> should and should not try to read. If I am a solver developer I  
> would assume that I should be processing ALL of the OSoL file. I am  
> pretty irritated if I get useless information. This is what I keep  
> coming back to: OSoL should only contain information relevant to the  
> solver and OSrL should only be information coming back from the  
> solver. We had things correct with version 1.0 and then really  
> screwed up in going to 2.0. Indeed, I would favor a modification to  
> your previous option 4 in that when we do a remote_solve()  we  
> package the OSoL inside OSpL, then strip out the OSoL and send it to  
> the solver.

I would accept that as a friendly amendment.

> Having OSpL information inside OSrL and OSoL is fundamentally wrong  
> in my opinion.

> My Mantra: "OSoL should only contain information relevant to the  
> solver and OSrL should only be information coming back from the  
> solver."
>
> Cheers
>
>
>
>
> -- 
> Kipp Martin
> Professor of Operations Research
> and Computing Technology
> Booth School of Business
> University of Chicago
> 5807 South Woodlawn Avenue
> Chicago, IL 60637
> 773-702-7456
> kmartin at chicagobooth.edu
> http://www.chicagobooth.edu/faculty/bio.aspx?person_id=12825325568
> http://projects.coin-or.org/OS
>
> Sent without Blackberry, Droid, iPhone, or any other
> wireless device.
> -- 
>
>



-------------------------------------------------------

Horand I. Gassmann, Professor

School of Business Administration, Dalhousie University
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