I have 128 MS SQL servers I need to add into my snort conf. I want to know if anyone has any info or experiences (good or bad) with this.

The servers cannot be added by subnet as they are scattered over a large network.

To sum it up:
What are the perfomance problems with adding 128 ip addresses to the SQL_SERVERS variable in the snort.conf? Has anyone tried this with success? At what number did you start to experience performance hit?