[imslavko]

Thoroughly enjoyed the article since I have heard about Neon but never understood what it offers on the technical level over other PG-compatible projects.

The article mentions that a consequence of separating storage from compute is that compute nodes cache hot pages in memory and load cold pages from object storage (like S3?) when needed. Does anyone know what are the consequences of this decision. In case of a query that touches multiple rarely used pages, would that incur high latency and ingress? How does that penalty compare to a vanilla postgres running on AWS and storing pages on EBS?

[nikita]

(neon ceo) Yes you will have an S3 fetch latency for downloading a layer file for such data. However we don't page out aggressively so it's a very unlikely event. Most of the time you will be fetching from a locally attached SSD which is superior and more predictable than EBS.

Where it works super well is the long tail of small and rarely used database - it pushes our costs way down.

Another advantage is that if the whole region goes down the S3 copy survives.

Finally if you separate storage and compute you can be serverless and scale to 0.

[imslavko]

Thanks Nikita!