Can't backup using S3 multipart

[RMartinOscar]

Can't backup a server if there's not enough space to archive the whole server.
Multipart should backup 5GB at a time, upload it, remove the temp archive and backup the next 5GB without having to create an archive the size of the server and split it afterwards.

The panel won't ever get that the backup failed either, it will be stuck on loading forever

[strich3]

same here, BACKUP_MAX_PART_SIZE just breaks it completely