Convert the traverse method of the problem space of the remove_finished_goals from BFS into a DFS (stack->queue). #1853
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…ed_goals from BFS into a DFS (stack->queue). Profile shows that the majority of the CPU time is spent in construction and destruction of a tree (std::set), which a bigger chunk is coming from mostly caused by copy construction and destruction followed after that. The problem space that this function is navigating is big enough that the data structure used cannot be simplified (four sets to track the state of traversal), but if we change the iteration from a BFS into a DFS, we get the benefit to avoid the copy, but rather being able to keep the increment and decrement diff of each iteration and only remember those, which will help avoid copying massive data structures which is super costly. I've tested out whether converting containers into an unordered_set helps, but I only saw some differences that could be considered as a noise, so I'd rather not have those changes. This change doesn't affect any existing tests. PiperOrigin-RevId: 707493506
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Convert the traverse method of the problem space of the remove_finished_goals from BFS into a DFS (stack->queue).
Profile shows that the majority of the CPU time is spent in construction and destruction of a tree (std::set), which a bigger chunk is coming from mostly caused by copy construction and destruction followed after that.
The problem space that this function is navigating is big enough that the data structure used cannot be simplified (four sets to track the state of traversal), but if we change the iteration from a BFS into a DFS, we get the benefit to avoid the copy, but rather being able to keep the increment and decrement diff of each iteration and only remember those, which will help avoid copying massive data structures which is super costly.
I've tested out whether converting containers into an unordered_set helps, but I only saw some differences that could be considered as a noise, so I'd rather not have those changes.
This change doesn't affect any existing tests.