I have to move a business application into the cloud, therefore cost is one of my biggest concerns.
DynamoDB seems to be a good option, while a big part of our data is able to migrate from relational database to NoSQL. It's said, AWS DynamoDB is cost-efficient. What does that actually mean?
Our application executes a query which returns about 100k rows several times a day. Amount of rows written can be assumed the same. The database is hosted now on a fairly low hardware, which can be compared to
t2.medium instance. On-demand (which is not the most cost-effective) database instance with PostgreSQL would cost ~ $55/month. Each time the query takes about
10 sec to execute.
Let's see to what the calculator says.
DynamoDB bill depends on the throughput.
10 sec is not the point, let's say we can wait a whole minute. The query returns 100k rows. That means we need a peak throughput of
1667 reads/sec (assuming items are less than 1 kb), and the same write throughput.
The calculator says:
Estimate of your Monthly Bill ($ 859.39).
15 times more expensive than RDS (and still 6 times slower).
Am i calculating that in a wrong way? Is there something out of my scope? Or, probably, DynamoDB is not suited for this kind of task?