Inverted Index Compression and Query Processing with Optimized Document Ordering

Inverted Index Compression and Query Processing with Optimized Document Ordering is a paper describing the state-of-the-art compression techniques for inverted list data structure, after document re-ordering. A reference reading paper.

I wonder if this work can be extended by taking into account the modern search engines are storing all the index in memory. This is also including inverted lists. Therefore, one can explore the benefits of having different hierarchies of memory.