Switch configuration for IDS/IPS recommendations

Hello,

I am adding an IDS solution to our EX4400 swithing network. We would like to set up the IDS unit on a mirror Port as Listening to activity on the network. We have approximate 15 VLANs, but only need to collect information from 2 VLANS.

What is the recommendation on Port Mirroring. VLAN, Ingress port , Egress port? I am looking at the VLAN mirror, will that be too much for one port to mirror?

Thanks