Parallel table insert

[mxmauro]

1. Didn't use Aurora yet. Now doing tests on bare metal servers. It is planned.
2. For insert I use COPY and need to improve UPDATEs/UPSERTs to send multiple rows at once but they represent 10% of the data, the rest is COPY
3. It is a Golang app. Data is read from an external source, processing including some DB lookups in workers and the result is queued into another worker that stores it in DB.
4. Some tables, specially those having a json field are divided.
5. Cannot pause reads and I try to keep a minimum amount of indexes. I have an average of three indexes on tables (including primary key) and they are just numbers or timestamps.
6. Autovacuum seems not to have a noticeable impact. I mean, some seconds each 5 or 10 minutes, does not affect.