I want to know if there are charges for uploading/dropping files in an S3 bucket created in EU region from a lambda function running in the US region.

Also how much of a performance hit it is, to have lambda function and the S3 bucket to be present in these two different regions.

Please help!!

CodePudding user response：

There's no charge for data transferred into S3, but you would be charged for data transferred from your Lambda function outside of the region the function executed in (charged at EC2 data transfer rates). You're also charged similarly for data into a Lambda function, if that data originates from outside the Lambda function's region.

For performance, I'd recommend that you test it and also see what the internet has to say about cross-region write performance to S3 (e.g. takipi/aws-s3-speed). Also, consider S3 Transfer Acceleration and Multi-Region Access Points.

The configured RAM size of your Lambda functions will impact their network bandwidth, so consider testing with large RAM Lambda functions.

And, generally, be aware of S3 Performance Guidelines.

You might also consider writing to an S3 bucket in the same region and have S3 replicate it cross-region.