[Coin-lpsolver] CBC LP Solve Times

[Vishnu Erramilli]

Hi,

I have been working with a problem with the following characteristics (as
given by the CBC pre-solver): 47333 rows, 139880 columns, 1714427 elements
and there is an issue related to LP solve times (using the clp solver):

1) It took 37703.8 seconds to solve the LP problem on CBC. It seems to be
taking too much time because I ran the same problem on two different
solvers and one took ~2000 seconds and the other took 30 seconds which
leads me to conclude that there is definitely some setting issues with my
current CBC executable.

2) I am using the cbcExampleSample2 exe to solve the problem.

Is there any reason why an LP could have such a drastic difference in
solve times? Is there a CBC executable that any on this discussion board
use that I could use to reduce the solve times?

I think there is definitely some issue if the LP is taking 10 hours to
solve. I would be thankful if anybody could point me in the right
direction as regards to settings/exe's of the CBC solver that could
optimize the solve times.

Thanks,

Vishnu