[Ipopt] Memory limitations in Matlab-interface IPOPT when using MA27

[Lemoine, Roberto]

Dear IPOPT developers/users:

I have a question. I am using the Matlab-interfaced version of IPOPT v.3.10.0 (run with Matlab R2011b in a computer with Windows 7), successfully compiled as described in the Interface website:

bandersnatch.dyndns.info/~djr/ipopt_compile_steps.pdf

My optimization problem is relatively small (1000 degrees of freedom or less). However, IPOPT solves the problem successfully only if I use the linear solver MA57 (I have METIS also installed). However, when I use MA27, IPOPT fails to start iterating, and shows the failure message:

EXIT: Not enough memory

This does not happen with MA57 (even MUMPS makes it to start iterating, but fails after some iterations due to problems in the restoration phase). I have played around by increasing the parameters ma27_liw_init_factor, ma27_la_init_factor and ma27_meminc_factor, and the problem remains. 

Does anybody have an idea why MA27 could be having this problems, while MA57 not? Is there a difference in the memory management of the solvers? Thanks a lot in advance.

Best regards,


Roberto Lemoine-Nava

Lehrstuhl für Systemdynamik und Prozessführung
Fakultät Bio- und Chemieingenieurwesen
Technische Universität Dortmund
Emil-Figge-Str. 70
44221 Dortmund

Tel.: +49 (0) 231/755-5171