Personally I, rather than using magento default functionality to take backups, I rely on doing it manually on server level. I have made a sh script (on linux server) which does this periodically for me, get downloaded to a backup server(or my machine) and got deleted when the download is finished. I rely on this because i dont want to make my setup heavy with span of time.
cat app/etc/local.xml
Get db credentials from here
mysqldump -u user_name -ppassword database_name > path_to_document_root/database_name.sql
Take database dump and put in document root (or any place you wish)
tar -cvf backup.tar site_folder/
Compress the site containing files and database from step 2
gzip backup.tar
This is optional, if you wish to compress it in more smaller size
Download or transfer files using scp or download link. May this help someone looking for an alternative process.