Thanks for the input guys. It's just getting worse. I ending up backing the Who's Online window from 10 down to 5 minutes just to keep the viewable list manageable... But even that is no longer tenable. A little bit ago, for a 5 minute period, I had just shy of 1000 guests. This on a near dormant forum. CPU usage is creeping up and I'm starting to get resource warnings.
I just took the drastic step of changing Guest permissions to not be able to read threads. This immediately eliminated the inundation.. but it's obviously not ideal as search engine visibility is now nill. This probably won't be a permanent change.
The Bot-scape has obviously ramped up dramatically in recent months. I wish there was a way to curtail it. Yes, I know about the robots.txt protocol, but you can't place blocks / rules in there if you don't know who the bots are. These all show up as normal browser user-agents. I suspect many disregard the robots.txt rules anyway.
Exasperated.
