We have explored Elastic File Storage (EFS - somewhat expensive) and synchronized S3 storage across multiple EBS volumes (prone to sync issues), though we have endless issues with various aspects of s3fs (S3 Fuse) at the scale we use it, our apps need the functionality.
We need adequate file uploading performance for 5 (Five) auto-scaled Memory-Optimized EC2 instances (LB-ed web servers) on a VPC that share identical file system structure to "assets" that are managed by end-users and maintained by the application.
A potential solution that we have not explored to leverage our CloudFront CDN configuration for files that could be as large as 2GB in edge cases, or as many as 600 files that vary from 5MB to 100MB each per "page" for users to review/edit. This seems problematic at scale, just as much if not moreso than S3FS is (if its even a viable option at all).
Leaning towards cost efficiency, but still with hardy considerations for performance:
is EFS a viable and cost-effective replacement option for S3FS functionality?
cost-controls of massive EBS Volumes is a concern, though not ruled out as a viable option, but is the performance going to be worth the added costs?
is CloudFront capable of handling such a load as described?
is there a better option that we have been missing that we may want to explore?