Not with AWS. If you don't have AWS as a requirement, go for it.
> i3.16xlarge
An i3.16xlarge still won't hold a 20TB dataset in memory. You are going to see more variance in latency if you have a working dataset too big to fit into memory.
As far as getting superior performance out of an i3.16xlarge, that's fine if you have the expertise and resources to run PG yourself. However you're going to need replication, which will increase that cost. You're going to need failover mechanisms, backup, etc.
We have preferred RDS for Postgres because it gives us something operationally simple. We've found DynamoDB to be even simpler operationally and have more predictable performance. We have frequently considered running a self managed PG instance and have decided against it for our use case.
Ok let's try :)
Did I ever claim on 48TB on AWS ?
You are seriously claiming DynamoDB will be holding full 20TB in RAM if yes I have a bridge to sell you :).
The price for i3.16xlarge was quoted for 2 instances the IOPS used for calculation is 1/8th of actual max IOPS that instance can do.
When presenting an alternative to DynamoDB, AWS is an implied part of presenting that alternative. While the original article does suggest an alternative outside of AWS, it properly qualifies it as a competitor offering. Regardless, I don't care what was and wasn't claimed. It's not important.
> You are seriously claiming DynamoDB will be holding full 20TB in RAM
No. I'm claiming that DynamoDB will have predictable and consistent latency characteristics at 20TB. The related claim is that an RDBMS will not have consistent latency characteristics if the working dataset does not fit in memory.
"When presenting an alternative to DynamoDB, AWS is an implied part of presenting that alternative". If that is the way you guys operate well ... We run things in AWS, on prem and in GCP. Our AWS spend is over 3 mil. per month things that require hard latency guarantees are def. not running in AWS. Nothing is AWS has "predictable and consistent latency characteristics" simply due to the nature of how they operate.
> You can get a box with 48TB RAM
Not with AWS. If you don't have AWS as a requirement, go for it.
> i3.16xlarge
An i3.16xlarge still won't hold a 20TB dataset in memory. You are going to see more variance in latency if you have a working dataset too big to fit into memory.
As far as getting superior performance out of an i3.16xlarge, that's fine if you have the expertise and resources to run PG yourself. However you're going to need replication, which will increase that cost. You're going to need failover mechanisms, backup, etc.
We have preferred RDS for Postgres because it gives us something operationally simple. We've found DynamoDB to be even simpler operationally and have more predictable performance. We have frequently considered running a self managed PG instance and have decided against it for our use case.