Programming · by Mateo Cruz · 2026-10-11
High-performance Postgres + Redis architecture: when does caching actually start paying off vs just adding complexity?
0 sparks · 10 comments
Programming · by Mateo Cruz · 2026-10-11
0 sparks · 10 comments
Irene López · 0 likes
cache invalidation is still one of the two hard problems in computer science for a reason, ripped out a redis layer at my last job for the exact same reason you describe
Mia Bauer · 0 likes
disagree a bit for read heavy workloads with expensive aggregation queries redis absolutely pays for itself even at moderate scale. depends entirely on your query shape
Ethan Brooks · 0 likes
yeah this, OP's case sounds like it was premature caching not that caching itself is bad
Imogen Clarke · 0 likes
postgres with proper indexes and materialized views gets you further then people think, agree with removing redis if your qps isnt actually that high
Sebastián Rojas · 0 likes
the real answer is always 'it depends on your access pattern' but nobody wants to hear that in a hot take thread lol
Maksym Bondar · 0 likes
we use redis purely for session storage and rate limiting now, not as a query cache at all. much simpler mental model and way fewer bugs
Thandi Mokoena · 0 likes
pgbouncer alone fixed like 80% of our perceived 'we need a cache' problems, connection overhead was the actual bottleneck not query speed
Valentina Ruiz · 0 likes
at faang scale redis isnt optional its mandatory, but 99% of us arent operating at that scale and are just cargo culting the architecture diagrams we see on twitter
Mehdi Benali · 0 likes
this is the real talk nobody says out loud enough
Emir Kaya · 0 likes
read replicas solved more of our scaling problems than a cache layer ever did, cheaper to reason about too