Extra long time computation with free rotations in irregular

[bbeaulant]

Hello Florian,

After trying the last commits, I notice a long time computation (> 30 seconds) when using free rotations on the following instance.json (the deer).

The following method consume all the time : packingsolver::irregular::compute_item_type_rotations

[fontanf]

Hi,

Thank you for reporting the issue. It should be fixed in b4bc59a

[bbeaulant]

Thank you, Florian.
It is now better, but it's still take more time than before. Is it what you expect ?
The same input, with free rotation take now around 15 seconds to find a solution similar the one that took 5 seconds few days ago.

[bbeaulant]

Hmm, but it take less than 5 seconds if I use tree search only.

[fontanf]

That looks like your processor having less cores that the number of threads used by the solver

[bbeaulant]

As I know my processor has 8 cores. So is ti preferable to always force tree search only ?

[fontanf]

Maybe it would be better to reduce the CPU requirements instead. Could you try to comment the last two directions in each case here:

packingsolver/src/irregular/optimize.cpp

Lines 207 to 251 in b90ded3

	} else if (instance.number_of_bins() == 1) {
	if (instance.objective() == Objective::BinPackingWithLeftovers) {
	switch (instance.parameters().leftover_corner) {
	case Corner::BottomLeft: {
	directions = {
	BranchingScheme::Direction::LeftToRightThenBottomToTop,
	BranchingScheme::Direction::BottomToTopThenLeftToRight,
	BranchingScheme::Direction::LeftToRightThenTopToBottom,
	BranchingScheme::Direction::BottomToTopThenRightToLeft,
	};
	break;
	} case Corner::BottomRight: {
	directions = {
	BranchingScheme::Direction::RightToLeftThenBottomToTop,
	BranchingScheme::Direction::BottomToTopThenLeftToRight,
	BranchingScheme::Direction::RightToLeftThenTopToBottom,
	BranchingScheme::Direction::BottomToTopThenRightToLeft,
	};
	break;
	} case Corner::TopLeft: {
	directions = {
	BranchingScheme::Direction::LeftToRightThenBottomToTop,
	BranchingScheme::Direction::TopToBottomThenLeftToRight,
	BranchingScheme::Direction::LeftToRightThenTopToBottom,
	BranchingScheme::Direction::TopToBottomThenRightToLeft,
	};
	break;
	} case Corner::TopRight: {
	directions = {
	BranchingScheme::Direction::RightToLeftThenBottomToTop,
	BranchingScheme::Direction::TopToBottomThenLeftToRight,
	BranchingScheme::Direction::RightToLeftThenTopToBottom,
	BranchingScheme::Direction::TopToBottomThenRightToLeft,
	};
	break;
	}
	}
	} else {
	directions = {
	BranchingScheme::Direction::LeftToRightThenBottomToTop,
	BranchingScheme::Direction::BottomToTopThenLeftToRight,
	BranchingScheme::Direction::RightToLeftThenTopToBottom,
	BranchingScheme::Direction::TopToBottomThenRightToLeft,
	};
	}

[bbeaulant]

Hello Florian,

This seems to reduce the time in half. But tree search alone remains slightly faster.