Originally posted on Substack
edit: this blogpost was initially wrong when I published it. Thanks to some comments I got, I learned I didnāt fully understand TrueTime or Spanner ā Iāve spent some time learning and understanding the core concept again, and have updated this artifact. This is an externalized resource for me that I hope can be helpful for others.
When I was reading the famous paper on Spanner, Googleās globally distributed linearizable database, I really struggled with the concept of TrueTime, which is a core component of why they were able to get their guarantees. After trying to wrap my head around it, I created the following artifact (IMO, TrueTime deserves a mini-ish paper or post on its own):