I only have one site in the home directory. This site is less than 300MB. When I back it up in softaculous, the backup takes so long it eventually gets a timeout error.
I checked /softaculous_backups/ and see the file is 4.5GB in size. I have removed this file and attempted to backup several times and still the same results.
Sir when an installation is in the root of home directory. Softaculous takes backup of the entire public_html directory. Also is your database huge ? The size of the backup will include both the files as well as the database.