为什么使用AWS DynamoDb“Hello world”会产生读/写警报？

I'v started to play with DynamoDb and I'v created "dynamo-test" table with hash PK on userid and couple more columns (age, name). Read and write capacity is set to 5. I use Lambda and API Gateway with Node.js. Then I manually performed several API calls through API gateway using similar payload:I'v started to play with DynamoDb and I'v creat