Yes, b+trees are more performant for reading compared to skip-list because of better data locality on memory/disk. But SL better at insertion and sequential rea

Yes, b+trees are more performant for reading compared to skip-list because of better data locality on memory/disk. But SL better at insertion and sequential reads. 255 GB is a simple trade-off between disk space required per record and the ability to manage large data-sets since SL is a not very space friendly data structure) Although I think 255 GB is good enough in many use cases.