I have been backing up a MySQL database for several years with the command:
mysqldump myDatabaseName -u root > myBackupFile.sql
The backups have appeare
mysqldump --skip-extended-insert works but can reduce performance by 100x on restore, making it not a viable choice.
When you do the backup, max_allowed_packet is ignored by mysqldump (by design?) The actual complement is net_buffer_length. So make sure your max_allowed_packet is bigger than your net_buffer_length and it should work. As in:
mysqldump -u root --net_buffer_length=100k oldDB > backup.sql
mysql -u root --max_allowed_packet=10M newDB < backup.sql