Does IBM ILOG CPLEX Optimization Studio impose any limit on the number of variables when solving optimization problems?

Question

I am solving an optimization problem in cplex opl. I have formulated the problem as mixed integer cone programming model. I want to ask is there any limit on the number of optimization variables whilw solving the optimization problem.

Is there any limit on the number of optimizing variables while solving the optimization problem. Why is it taking more than 1 hour to give optimal result?

Answer 1

There is no size limit but large model may take hours or more.

See tech note for some tips to improve your model which starts with

Question

How do I select non default parameters to tune CPLEX's performance on a difficult mixed integer program? Answer

Because of the combinatorial nature of integer programs, CPLEX users may have more trouble getting good performance with integer programs than with linear or quadratic programs. CPLEX has many parameters that allow users to customize the way the CPLEX branch and bound algorithm operates. While this variety of parameters provides many different ways to improve performance, a user cannot realistically experiment with all the possible combinations of parameter settings. Therefore, we recommend the following tactics for solving MIPs with CPLEX 11.0 or later. Many of these recommendations will also be effective with earlier versions of CPLEX. However, we would highly recommend that you upgrade to the most recent version of CPLEX if you are using an old version; doing so may yield more performance improvements than adjusting parameters of an old version. Also, if you are running a newer version of CPLEX on an old model that previously solved effectively with non-default parameter settings, try the default settings with the newer version. Refer to the CPLEX User Manual if you need additional information about any of the terms mentioned.