多区域 Postgres 延迟问题 Azure

Question

Architecture which we are using currently is as below

Private Web App Services hosted in US Region and India Region. Both the apps are behind the respective App Gateway, this app Gateway is behind the front door which helps us serve the request from the nearest app gateway. But Both apps uses the same postgres which is present in US region.

Now our issue is when we hit the api from US response time is less then 2sec whereas when we hit the api from India region it takes 70sec.

How can we reduce the latency?

Actually, the problem is the APIs does write operation due to which we cannot a read replica.

Answer 1

There a few things you can do

1- Add a cache layer to both regions and rather than querying directly on DB, check if the data is available in the cache first, and if it's not, get it from DB and add to the cache layer.

2- Add a secondary database on India region which will be a read only.

PS: You may have stale data with both approaches so you should sync properly according to your requirements