Snort using 90% CPU

I'm running v18 EAP3.  This is the first time I've seen my CPU running at 99% to 100%.  When I run "top" from the advanced shell, snort occupies the top 4 positions at 97%, 91%, 90%, and 84%.  I am using "web proxy" instead of DPI and I've disabled "ATP".  No difference.