in my opinion your question is too generic to get an accurate answer. To educate yourself reading Postgres docs or some good books would be in my opinion the best way to give an answer yourself to your own question. Then you can still post to the ML on some specific setting (postgres performance ML is the best place).
Much of the requirements depends on the expected load on the database and what kind of usage you will do, such as OLTP or DWH/BI. Also the database size is important to fit in the picture.
As rule of thumb, you want all your installations to be identical in terms of hardware specs. CPU should be able to serve your queries and your clients, so you must have enough cores to serve the expected number of connections without degrading performances.
About RAM, the more the better, but if you have enough to fit your db (or the part you use of your db) in RAM, you will probably avoid many of your problems about disks performances.
Do not forget disks, RAID controllers, networking, SLA, SLO, HA, DR..
OT: I would use newer Postgres than 9.6 if I were you, unless you have good reasons to use 9.6.
regards,
fabio pardi
On 04/06/2020 11:36, Praveen Kumar K S wrote:
Hello All,
I'm looking for hardware configurations to set up 1 master and 2 hot-standby slaves using 9.6 in one DC. Also, I need to have DR with the same setup with cross-site replication enabled. I went through a lot of docs/blogs suggesting 4cores and at least 4/8GB RAM. But I'm looking for help on how exactly one can justify the hardware requirements, like a formula ? Please advise.