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5. J+-Tree: A New Index Structure in Main Memory
6. T-Tree or B-Tree: Main Memory Database Index Structure Revisited:
Under no concurrency, J+ tree >= T tree > B Tree. B+ tree was originally found for disk based indexes. However for concurrent indexing mechanism, B+ tree is still found desirable to be efficient compared to J+ tree and T tree since B+ tree since it provides cache based optimization by compressing more indexes within a single node.
7. Concurrent B-trees with Lock-free Techniques (paper)
Uses B-list tree with pointers linking siblings. During concurrent insertions and deletions, they use the sibling pointers to maintain consistency.
Discussion
Under no concurrency, J+ tree >= T tree > B Tree. B+ tree was originally found for disk based indexes. However for concurrent indexing mechanism, B+ tree is still found desirable to be efficient compared to J+ tree and T tree since B+ tree since it provides cache based optimization by compressing more indexes within a single node. Concurrent Main Memory Aware Design
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