The Three DynamoDB Limits You Need to Know
there are a few limits you must understand to model properly in DynamoDB. If you’re not aware of them, you can run into a brick wall. But if you understand them and account for them, you remove the element of surprise once your app hits production. Those limits are: The item size limit; The page size limit for Query and Scan operations; and The partition throughput limits. Notice how these limits build on each other. The first is about an individual item, whereas the second is about a collection of items that are read together in a single request. Finally, the partition throughput limit is about the number and size of concurrent requests in a single DynamoDB partition.
I just ran into the last one on a pretty massive table we own, so this is worth bookmarking…(tags: dynamodb aws storage gotchas limits ops architecture)