I have configured my discourse installation to upload files to S3, but am having unusual delay when uploading large files. To preempt the question: yes, I have configured nginx and discourse to accept arbitrarily large files (in fact, I made a thread that sussed out a bug preventing uploads larger than 10MB due to a hard coded limit on the frontend).
When I upload a large file (50MB-2GB), the uploader shows progress that crawls to 100% at the speed that seems right for my connection and filesize, but then the bar gets stuck at 100% for a very long while, and may never complete. Some files (~25MB) seem to ‘upload’ for x minutes, then stall for around x + ~3 minutes, then ‘finish’ uploading and are available from S3. Others (~100MB) will seem to upload for x minutes until the bar says 100%, then stall indefinitely (or at least longer than overnight).
I am happy to investigate this issue, and will even contribute a PR to patch it, but would like to check-in to see if this is a known feature/limitation, and if anyone is already working on this bug.