[gresrun]

YouTube used to use a MySQL-based system called Vitess[0]. It no longer uses it and has migrated to Spanner.

[0]: https://vitess.io/

[Thaxll]

Thanks for the update! I found more details there: https://opensource.google/projects/vitess

> How Google uses Vitess

> Vitess was serving all YouTube database traffic from 2011 to 2019.

[wikibob]

Ah this is interesting. Do you have any references on their migration to Spanner?

[buro9]

gresrun works at YouTube, if by reference you mean citation then his comment is it.

[jjnoakes]

wikibob was probably looking more for public documentation about the why and how rather than confirmation that the statement is true.

[wikibob]

Yep, I love watching conference talks or reading Twitter threads, papers, etc about these kind of migrations.

[owaislone]

Probably because Youtube was using MySQL before being acquired and switched to a better, probably fully managed DB that was much easier (free?) to maintain and scale.

[annexrichmond]

was that migration a technical decision or a political one?

[haimez]

This is one of those scenarios where the answer is likely to be “both”, but I doubt you’ll get anyone discussing YouTube internal architecture in enough detail to be satisfying. Just look up what Vitesse is and compare what that implies in terms of operational complexity to using something like spanner if you want a straw man technical rationale.