Please excuse if this question isn't as clear as it should be, but I'm a Dev (not a System Administrator) who is trying to help out with an issue we're seeing. We just migrated the hosting of our sites to a data center (faster servers and more bandwidth). All of the data from the database is loading faster, but the CSS and image files seem to have slowed down considerably. The pages will load all of the data, but it takes some time before all of the images download and render (images are hosted by same web servers). Note, that we're now virtualized too (VMWare). One, are there any settings or known issues that can quickly help me identify the cause of the slow down? Two, if not, what are some things I can do to try and isolate the cause of the lag?
First thing I'd try is yslow in Firefox to get some numbers on response time. It may also give you some tuning tips. If your website was in-house you may have never noticed the latency caused by lots of images and lots of CSS files. (IIRC some web browsers limit themselves to 4 simultaneous download operations, so a page with lots of small assets is slower than a page with a few large assets)