I have seen many PostgreSQL benchmarks having solid performance with TB data but my real world experience is the complete opposite.
Here are some of the main issues that I have encountered so far:
1. Queries on large tables (around 10 GB) are slow even when "index only scan" is used because of MVCC and the way postgreSQL manages concurrency.
2. Hot-standby instances can't be used for anything serious since all queries are dropped regularly (I believe it's not safe to use "hot_standby_feedback" config to overcome this issue).
3. It is not possible to have tables with heavy "update" workflows. (because of simultaneous autovaccum execution)
I would be very happy if anyone could show me that I am wrong.
Here are some of the main issues that I have encountered so far:
1. Queries on large tables (around 10 GB) are slow even when "index only scan" is used because of MVCC and the way postgreSQL manages concurrency.
2. Hot-standby instances can't be used for anything serious since all queries are dropped regularly (I believe it's not safe to use "hot_standby_feedback" config to overcome this issue).
3. It is not possible to have tables with heavy "update" workflows. (because of simultaneous autovaccum execution)
I would be very happy if anyone could show me that I am wrong.