[SCIP] concurrentopt and warm starts

[Robert Lion Gottwald]

Hi Peter,

thanks for reporting this problem, you did nothing wrong. For fixing the
issue you can try the attached patch. The problem will probably also be
fixed in the next (bugfix) release of SCIP.

Best,
Robert

On 2/1/19 3:25 PM, Purple Break wrote:
> Hi,
> I am using SCIP 6.0.1 on Linux.
> is it possible to make use of warm starts when using concurrentopt?
>
> Using the interactive optimizer it seems to accept the solution but
> then ignores it during solving:
>
> read problem <x.lp>
>
> primal solution from solution file <x.sol> was accepted as candidate, 
> will be checked when solving starts
>
> SCIP> concurrentopt  
> 1/1 feasible solution given by solution candidate storage, new primal
> bound 2.288640e+06
>
> starting solve in concurrent solver 'scip-7'
> starting solve in concurrent solver 'scip-4'
> starting solve in concurrent solver 'scip-6'
> starting solve in concurrent solver 'scip-8'
> starting solve in concurrent solver 'scip-3'
> starting solve in concurrent solver 'scip-5'
> starting solve in concurrent solver 'scip-2'
> starting solve in concurrent solver 'scip-1'
>  time | mem |  dualbound   | primalbound  |  gap   
> $11.3s|3829M|      --      | 6.127008e+06 |    Inf 
>  12.5s|3878M|      --      | 6.127008e+06 |    Inf 
>  17.6s|4251M|      --      | 6.127008e+06 |    Inf 
>  20.6s|4433M|      --      | 6.127008e+06 |    Inf 
>  29.8s|4791M|      --      | 6.127008e+06 |    Inf 
>  30.1s|4814M|      --      | 6.127008e+06 |    Inf 
> $1164s|6801M| 1.428576e+06 | 2.745312e+06 |  92.17%
>
> As you can see: the 8 solvers are not using the primal bound 2.288640e+06
>
> Thanks,
> Peter
>
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