Originally posted by: gfacchet

Hi,
I'm working with MATLAB and CPLEX (academic licence) for solving both linear and quadratic minimization.
In the first case I do not have any problem but for the second (quadratic), I cannot free the matlab memory which has been occupied after cplexqp running.
Since I must screen several combinations, after about 500 cplexqp running (in a function), the memoryload reach 100 and the program stop working. I even make a "clear all" (after having saved the results up to that point) but the only way to reset the memory load is to exit from MATLAB and restart again.
It is strange that this did not happened while I using cplexmilp.

I ask you how I can solve this problem
Many thanks
Giuseppe
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Originally posted by: SystemAdmin

What version of CPLEX do you use?
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Originally posted by: gfacchet

I'm using CPLEX 12.1 (academic licence, as I mentioned).
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Originally posted by: SystemAdmin

CPLEX 12.1 had a known issue concerning memory management. Does it help to set the number of threads to 1 or to set the environment variable MKL_DISABLE_FAST_MM to a non-empty value?
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Originally posted by: gfacchet

Sorry but I do not know how to set environment variable MKL_DISABLE_FAST_MM to a non-empty value.
Usually I run CPLEX in a Matlab code, for instance, by the command "cplexqp".
Is the variable you have mentioned in the cplex options structure?
thanks
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Originally posted by: SystemAdmin

No, it is a global environment variable.
On Windows you can change this via
Start -> Control Panel -> System
then go to the "Advanced" tab and click the button "Environment Variables". Add MKL_DISABLE_FAST_MM to the system variables and assign some non-empty value. Note that you have to restart matlab after this change.
On Linux/Unix system you can do

export MKL_DISABLE_FAST_MM=1

in the shell in which you start matlab. Again, you have to restart matlab (from the shell in which you did the 'export').

Remember to unset the variable if you switch to a more recent version of CPLEX or find that setting it does not help.
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