Spanner on a modern columnar storage engine
cloud.google.com
cloud.google.com
Apparently Ressi was meant to enter production in 2017 according to some older blog posts, so I'm not sure if this is a delay or the result of a long-running consolidation.
There are a few paragraphs about it in the SIGMOD '17 Spanner paper from Google
https://static.googleusercontent.com/media/research.google.c...