Images take forever to upload and render while using GridFS for MongoDB 4.X.X<

Description of the issue: After upgrading to Rocket.chat version 4.X.X., MongoDB 4.2.X and above some users reported slow image uploads and reduced performance in general.​ The main reason is the usage of GridFS for files uploading, it's becoming very slow with 60K+ chunks and it takes forever to upload images and a long time for the images to be visible once the image is there.

Note: GridFS is only sustainable if you are using the Retention Policy and only storing a small number of files per week which is not hefty but it is not recommended by us because it is not scalable.

Quick Solution: 1. Enter mongo shell ( command example for Docker)

docker exec -it mongodb mongo

2. choose rocket chat DB:

use rocketchat

2. After adding an index with the command below, it goes back to normal. db.rocketchat_uploads.chunks.createIndex( { files_id: 1, n: 1 }, { unique: true } )

Reference: https://github.com/RocketChat/Rocket.Chat/issues/23467#issuecomment-957126927