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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hi Ted,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">We have noticed that OsiCbcSolverInterface::branchAndBound() has a warning that says it is deprecated and that CbcSolver should be used instead.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Can you elaborate on what it means, how it hurts our performance and what are the consequences of using the deprecated Osi interface.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Ken<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Alon Shapira
<br>
<b>Sent:</b> Wednesday, May 14, 2014 6:33 PM<br>
<b>To:</b> Ted Ralphs<br>
<b>Cc:</b> cbc@list.coin-or.org<br>
<b>Subject:</b> Re: [Cbc] thread safety<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank you :)<o:p></o:p></p>
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<p class="MsoNormal">Alon<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><i><span style="color:#333333">Sent from my Verizon Wireless 4G LTE DROID</span></i><o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
<br>
Ted Ralphs <<a href="mailto:ted@lehigh.edu">ted@lehigh.edu</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">The answer is a qualified "yes". We have been successfully using Cbc to simultaneously solve multiple different problems in different threads by creating a CbcModel object and calling the branchAndBound() method. Using the wrappers in
CbcSolver.cpp does not seem to be thread-safe. Calling Cbc this way only works for solving one MILP at a time (though it is possible to use multiple threads to solve that single MILP). I don't recall the precise reason for this.<o:p></o:p></p>
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<p class="MsoNormal"><br>
Cheers,<br>
<br>
Ted<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, May 14, 2014 at 12:18 PM, Alon Shapira <<a href="mailto:ashapira@tower-research.com" target="_blank">ashapira@tower-research.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black">Hi,<br>
Is the cbc library (and the clp) thread safe ?<br>
What I mean is : Can two different threads solve (two different problems) simultaneously ?
<br>
Thanks,<br>
Alon<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
_______________________________________________<br>
Cbc mailing list<br>
<a href="mailto:Cbc@list.coin-or.org">Cbc@list.coin-or.org</a><br>
<a href="http://list.coin-or.org/mailman/listinfo/cbc" target="_blank">http://list.coin-or.org/mailman/listinfo/cbc</a><o:p></o:p></p>
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<br>
-- <br>
Dr. Ted Ralphs<br>
Associate Professor, Lehigh University<br>
(610) 628-1280<br>
ted 'at' lehigh 'dot' edu<br>
<a href="http://coral.ie.lehigh.edu/~ted" target="_blank">coral.ie.lehigh.edu/~ted</a><o:p></o:p></p>
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