Which of the following is MOST likely the cause of the application latency?
Amazon S3 throttles the rate at which uploaded objects can be encrypted using KMS keys.
The AWS KMS API calls limit is less than needed to achieve the desired performance.
The client encryption of the objects is using a poor algorithm.
KMS requires that an alias be used to create an independent display name that can be mapped to a KMS key.
Explanations:
Amazon S3 does not throttle the rate of object uploads with KMS encryption. Instead, it automatically manages the encryption process without explicit throttling.
AWS KMS has rate limits on the number of API requests it can handle per second. If the application is uploading a large number of objects, it may exceed the KMS request limits, leading to slower performance.
The client-side encryption algorithm is not relevant here, as the encryption is being handled by AWS KMS (server-side encryption), not the client.
While using an alias for a KMS key is a best practice for management and naming, it does not directly cause any performance issues. The key’s alias does not impact the upload rate or encryption performance.
My best guess is:
The AWS KMS API calls limit is less than needed to achieve the desired performance.