backup backup-strategies mysql mysqldump replication

How can I slow down a MySQL dump as to not affect current load on the server?

While doing a MySQL dump is easy enough, I have a live dedicated MySQL server that I am wanting to setup replication on. To do this, I need dumps of the databases to import to my replication slave.

The issue comes when I do the dumps, MySQL goes full force at it and ties up resources to the sites that connecting to it. I am wondering if there is a way to limit the dump queries to a low priority state to which preference is given to live connections? The idea being that the load from external sites is not affected by the effort of MySQL to do a full dump…