I can't answer this directly, but I thought I'd chime in with a possible alternative, or at least something else to test.
I'm using rclone with S3[1] (and others). There are commands[2] where you can use to just sync/copy/ files but it also has a mount option[3]. It also has caching[4] and other things that might help.
I'm using rclone with S3[1] (and others). There are commands[2] where you can use to just sync/copy/ files but it also has a mount option[3]. It also has caching[4] and other things that might help.
[1] https://rclone.org/s3/
[2] https://rclone.org/commands/
[3] https://rclone.org/commands/rclone_mount/
[4] https://rclone.org/cache/