I was reading up on Cop+ (Dansguardian GUI Addons for IP-cop).
The page say
Filter groups 2 and 3 have their own bannedsitelists and greylists but they use the same whitelists and phraselists as the default group1. If this is more complexity than you need, you can, for instance, configure them to use the same greylists as group 1. This will save RAM in your IPCop and simplify maintenance for you, the administrator.
I checked that endian did use different lists for different profiles, I thinking using common whitelist, pharselist and greylists will definitely same some RAM.
cheers!
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