I heard that rsync isn't the best one when creating the first backup in terms of performance. Instead it is the best for the later backups. So I wonder what are some better commands for creating the first backup, and what your usages for them are? Thanks!Reference:rsync isn't a good option for copying files to an empty destination.  If you're migrating data to an empty destination, you already know all  files need to be copied so the checking rsync does is  counterproductive and actually increases the time the transfer takes.  This is mentioned somewhere in the rsync man page or FAQ or something,  I think.
Creating the first backup
backup;rsync;file copy
rsync is great for keeping two directories up to date by comparing them and only moving over what had changed. You could totally use rsync for the first time. It just will obviously have nothing to compare against and just move everything over. So with that though in mind you could just use cp or scp if you're moving the files to a remote server.If you want more backup options like detailed changes and more control over your backups check out https://help.ubuntu.com/community/BackupYourSystem