Originally posted by: Falcon_G

Dear all

I have got a problem for which I generate the cuts in lazy constraint callback and a userCut callback.

The code works fine with a single thread.

 

with more threads:

Initially, I had an instance of IloFastMutext which was shared between them to lock and unlock.  I expected to work properly as I have done it in the earlier versions of cplex but this time did not and causes an exception which is not catched.

Therefore, i gave one separate instance of IloFastMutex to each callback  and after that it works fine with two threads.

 

As soon as I increase the number of threads to three 3 I get the same issue and execution ends with:

First-chance exception at 0x774745ce in bc-multi-thread.exe: 0xC0000005: Access violation reading location 0xfeeefeee.
Unhandled exception at 0x774615de in bc-multi-thread.exe: 0xC0000005: Access violation reading location 0xfeeefeee.
First-chance exception at 0x7745016e in bc-multi-thread.exe: 0x00000000: The operation completed successfully.
Unhandled exception at 0x774615de in bc-multi-thread.exe: 0x00000000: The operation completed successfully.
The program '[22708] bc-multi-thread.exe: Native' has exited with code 0 (0x0).
 

Again the exception is not catched in any of the following:

     catch(IloMutexProblem& e)
     {
         cout << "IloMutexProblem::" << e << endl;
     }
    catch (IloException& e) {
        cout << "exception::" << e << endl;
    }
    catch (...) {
        cout << "exception::" << endl;
    }  

 

I appreciate any constructive comment.

 

regards,

Shahin

 

 

 

 

 

 

#CPLEXOptimizers
#DecisionOptimization

Do the callback classes only access callback-local data or do they access global data? In the latter case having a different mutex for different callbacks will not prevent race conditions.

#CPLEXOptimizers
#DecisionOptimization