Setting cplex parameters in DoC execution

What is the best way to set cplex parameters when solving in DoC? Does it use settings in the .ops file while solving?


I started my work with a multi model architecture, since at the beginning, I had to solve a model iteratively. But after a while as the requirements changed need for iterative solving is gone. Now although there is no need for iteration I am still using the same code and using the multi model architecture to solve ONE model.


This, I thought would be beneficial, since it would let me change Cplex settings before calling for solving. However I am not sure, if the code I am writing is actually changing the cplex parameters as I wish.


My flow control MOD file has following code,


Here, although I am setting parallel mode () to -1 (Opportunistic) using When the solve starts, the Engine log say Parallel mode: Deterministic. Engine log is pasted below in blue. Please see text highlighted in RED in the Engine log. I wonder whether my method of setting cplex parameters is correct? How to make sure, the parameters I am setting are actually used by Cplex? Please advice.


I tried setting the entire OPS file using ‘applyOpsSettings’ (commented line in the code snippet above). But DoC execution crashes when it hits this line.


~~~~~~~~~~~~~~~~~~~~~~~~~~` Engine Log ~~~~~~~~~~~~~~~~~~~~~

Tried aggregator 5 times.
MIP Presolve eliminated 93454 rows and 265990 columns.
MIP Presolve modified 346768 coefficients.
Aggregator did 29404 substitutions.
Reduced MIP has 130371 rows, 198686 columns, and 679149 nonzeros.
Reduced MIP has 185476 binaries, 11551 generals, 0 SOSs, and 0 indicators.
Presolve time = 7.88 sec. (5836.23 ticks)
Probing fixed 78686 vars, tightened 819 bounds.
Probing time = 6.90 sec. (2136.75 ticks)
Tried aggregator 1 time.
MIP Presolve eliminated 3860 rows and 83168 columns.
MIP Presolve modified 38611 coefficients.
Reduced MIP has 126511 rows, 115518 columns, and 428018 nonzeros.
Reduced MIP has 102712 binaries, 11565 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.98 sec. (599.30 ticks)
Probing fixed 0 vars, tightened 481 bounds.
Probing time = 1.36 sec. (137.41 ticks)
Cover probing fixed 0 vars, tightened 1 bounds.
Tried aggregator 2 times.
MIP Presolve eliminated 802 rows and 5596 columns.
MIP Presolve modified 2793 coefficients.
Aggregator did 38 substitutions.
Reduced MIP has 125671 rows, 109884 columns, and 425901 nonzeros.
Reduced MIP has 97323 binaries, 11570 generals, 0 SOSs, and 0 indicators.
Presolve time = 1.06 sec. (696.52 ticks)
Probing time = 0.23 sec. (27.63 ticks)
Cover probing fixed 0 vars, tightened 1 bounds.
Clique table members: 282629.
MIP emphasis: balance optimality and feasibility.
MIP search method: dynamic search.

Parallel mode: deterministic, using up to 4 threads.
Root relaxation solution time = 13.54 sec. (6047.97 ticks)

        Nodes                                         Cuts/
   Node  Left     Objective  IInf  Best Integer    Best Bound    ItCnt     Gap

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