[Users] Limit migration bandwidth

Hi All, I have seen this question asked before and seen it answered but can't find it back on either the mailinglist or IRC, probably because I don't use the correct search term but can't dream up any new ones so I'm asking: How to limit the amount of VM's that can simultaneously be migrated and how to limit the bandwidth used by migrating VM's? Looked at vdc_options, engine-config but have run out of ides. Thanks in advance, Joop -- irc: jvandewege