Comment by vlovich123

For anyone curious this is about a 2023 paper proving that a 2022 theoretical hash table construction achieved not only an upper bound in performance in terms of time and space, the construction also achieved a lower bound. It’s a theoretical construction so not actually a practical one you’d find in your software toolkit (constants are too large for most applications, likely even realistic databases). The referenced “practical” IcebergHT data structure isn’t even one you’d likely encounter as it seems to be a research hash table focusing on persistent memory which isn’t hardware you typically would encounter.