MIPRAMPUP

Controls the strategy used by the parallel MIP solver during the ramp-up phase of a branch-and-bound tree search.

Integer

-1	Automatically determined.
0	No special treatment during the ramp-up phase. Always run with the maximal number of tasks.
1	Limit the number of tasks until the initial dives have completed.

-1

The branch-and-bound tree search starts from the single root node, and only through branching on this root node and the resulting child nodes, are enough active nodes created to produce sufficient tasks to keep all MIP workers busy. This is referred to as the ramp-up phase of a parallel MIP. In a typical MIP solve, the solutions found during the initial dives will typically provide a significant improvement over the root heuristic solutions. It can therefore be advantageous to let these initial dives run as fast as possible, by limiting resource contention. This can be accomplished by restricting the number of parallel tasks and thereby reducing the memory bus contention. The MIPRAMPUP control can be used to turn this initial task restriction of a parallel MIP solve on or off.

XPRSmipoptimize ( MIPOPTIMIZE).

MIPTHREADS, MAXMIPTASKS.