Originally posted by: PaulBerglund

I am calling CPLEX from MATLAB. I do a large number
of calls to CPLEX and over time my memory usage goes up
and up. It seems like there might be a memory leak,
whether in MATLAB, in CPLEX or in the interface between
the two I can't say.

Any ideas/suggestions?

I am using IBM ILOG CPLEX Optimization Studio V12.2
and MATLAB version 2009b, on Windows XP.

Paul Berglund
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Originally posted by: belenmartin

Hi Paul,
I am having the same problem.

I am using the same IBM ILOG CPLEX optimization Studio V12.2
and Matlab 2007b on windows 7.

I have tried to save my data on disk, clear all and load them again, and it didn't solve the problem.
Belén.
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#DecisionOptimization

Originally posted by: John Cui

So, how do you call CPLEX in matlab? By toolbox or Cplex class?
I recommend below code to reduce memory usage in matlab:

for i=1:10
   cplex=Cplex();
   cplex.Model.A = your_A;
   cplex.Model.lb = your_lb;
   {...build your model...}
 
   cplex.solve();
   sol = cplex.Solution;
   clear cplex;
end

Is it helpful?

John Cui
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Originally posted by: belenmartin

I am currently using the toolbox, but i'll try your suggestion.
Thanks a lot,
Belén
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Originally posted by: belenmartin

Hi,
I've tried it but it didn't work.

I've done a small test problem, you can see how memory is rising up and up, no matter I'm clearing the objects.
load('prueba')
whos
for i=1:10
cplex=Cplex('name');
cplex.Model.name='name';
cplex.Model.sense='minimize';
cplex.Model.ub=inf*ones(size(L));
cplex.Model.lhs=-inf*ones(size(beq));
cplex.Model.Q = Qcost;
cplex.Model.obj = cost;
cplex.Model.lb = L;
cplex.Model.A = Aeq;
cplex.Model.rhs = beq;
cplex.solve();
sol = cplex.Solution;
clear sol
clear cplex.Model;
clear cplex
clear ans
memory
end

Thanks for your suggestions, anyway.
Belén
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: John Cui

Can you upload prueba file to here? Which I need to reproduce.
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Originally posted by: belenmartin

I thought I had done it.
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Originally posted by: belenmartin

You can find prueba.mat attatched to this post.
Thanks a lot,
Belén
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#DecisionOptimization

Originally posted by: PaulBerglund

For what it's worth I too am still having the
problem. I switched from using the toolbox
function to using the cplex class, but I am
still seeing gradually increasing memory use
for MATLAB. It is increasing fairly slowly;
by about 5MB for each invocation of a function
that makes on the order of 1000 calls to cplex
every time it is invoked.

The code I am using to call cplex is as follows:

cplex = Cplex('projection');
cplex.Model.sense = 'minimize';
cplex.Model.Q = F;
cplex.Model.obj = c;
cplex.Model.lb = lb;
cplex.Model.ub = ub;
cplex.Model.A = A;
cplex.Model.lhs=-inf*ones(size(b,1));
cplex.Model.rhs = b;
cplex.DisplayFunc = [];

cplex.solve();
x = cplex.Solution.x;
clear cplex;
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Originally posted by: SystemAdmin

Are you using the academic version of CPLEX 12.2? Is so then you are probably suffering from a known memory leak in the license handler.
The current recommended workaround is to reuse the CPLEX object as much as possible.
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Originally posted by: PaulBerglund

I changed to re-using the cplex object (I had been throwing
it away every time I used it) and now memory use grows a lot
more slowly. It still grows, though possibly not any faster
than it actually needs to do.

Thank you for the suggestion.

Paul Berglund
#CPLEXOptimizers
#DecisionOptimization