Yes. You can grab the ancestors shared and the leaf or subtree you want to modify exclusive. If all of your writers land in the root of the tree because it's a small tree, they all contend on the same lock.
Not really. But you could imagine hacks like forcing updates instead of logging to the first N-levels (N = 1 or 2) of the B-tree. I don't know how well that would work in practice. I do know that B-tree block contention…
Yes. You can grab the ancestors shared and the leaf or subtree you want to modify exclusive. If all of your writers land in the root of the tree because it's a small tree, they all contend on the same lock.
Not really. But you could imagine hacks like forcing updates instead of logging to the first N-levels (N = 1 or 2) of the B-tree. I don't know how well that would work in practice. I do know that B-tree block contention…