largish site, poor performance, what to do?
I've got a rapidly growing photopost installation - 12k photos, growing at a rate of about 2-3k per month lately. We've got multiple hundreds of categories and 50-100 concurrent users throughout the day, about 120k page views/day in the gallery. my poor server simply cannot handle the load and I've got database guys telling me that photopost "doesn't scale well". we've already optimized the indexing, I moved to a dedicated server a couple months ago and had hopes that this would solve my performance problems. Do I really need to pay $500+ per month (the going rate at my provider) to upgrade to a high-end machine and fast drives to host my not-so-large site? what can I do to improve performance?
I'm desperate at this point and would love to hear any ideas from those who've been through this. what about something like Turck MMCache? should I look for a different provider in hopes of getting a better deal somewhere else? can I optimize pp somehow? tia