can I limit connections per client? VisualSVNServer2.0.8

[EdwinTai]

We have a problem when someone update his workingcopies.If they use
update the project root which include many subfolders, VisualSVN
Server will slow down and nobody can do svn operation more.
Now I found only two people begin update,the server will stop
reponse.I use netstat to test connections.there are many connections
from the same client.
If I can setup connections per user.maybe I can fix the problem.any
ideas?