AWS IoT with Dynamodb or other solution

Question

I'm building a water leak detector for the days I'm out of my house, using an ESP-32. It's already working fine using AWS IoT saving the "pulses" (water flow) to DynamoDb.

But now I'm thinking if DynamoDb is the best solution here, because in those days I'm using the house it will generate 1 pulse per second (1 entry), which can represent thousands of entries per day.

My final solution should be having some dashboard to follow the usage of water, but mainly an alarm that I can set for specific date/hours that I'm not at home. I don't need to storage data for a long time.

With these information, my question is: should I be using other tool like CloudWatch instead of Dynamodb, that will provide me dashboard + alarm? Am I missing something to make the decision of doing this change?

thanks!

Answer 1

You can alarm on your Cloudwatch metrics which are generated for free from DynamoDB.

1 write per second remains in free tier on DynamoDB.

If you use custom Cloudwatch metrics then you would incur a cost to publish your metrics each second, and you would also lose some of the information you would store with each pulse.