Lykaon wrote:
But hybinet, are you ultimately saying that you don't think Apache will work as well for me? Because that was my original question. Certainly, if I can expect noticeable performance degradation, then I'll want to rethink using Apache.
I didn't mean to imply that Apache would be bad for you. I was just wondering why you want to move from lighty back to Apache, because most people on these forums want to move the other way around. If anything, Apache increases memory consumption. Whether or not this matters depends on how much memory you have at your disposal.
With only 5,000 hits per day, any web server would work just fine, as long as you configure it properly. Do you know whether your image files are being served directly by lighty or through a PHP script? You can usually tell by looking at the URL of the images. If it's the former, you can get significant memory savings (and possibly performance gains) by staying with lighty or nginx, but since you have plenty of memory this might not be a concern. If it's the latter, switching to Apache probably won't change anything memory-wise.
Another option, as @JshWright said, is to put lighty/nginx in front of Apache as a reverse proxy. This setup has similar memory and performance characteristics as lighty/nginx with fastcgi, but you also get to play with fancy Apache rewrite rules. If you want to have the best of both worlds and don't mind having some fun tweaking things, try this.