[Dean C]

Originally Posted by Marco van Herwaarden

I never even mentioned the word query.

But if you are going to add things like avatars, then this can have a big impact on performence (do they need to be resized?), memory usage (all these avatars into memory, retrieving from either disk or database) and bandwidth (all these images must alos be sent to the client).

Consider a board with over 1.000 users online.

If you have 1000 users online you're going to need your own dedicated server. If you have your own dedicated server you can probably use memcache, and put this kind of data in memcache because memory's so cheap.

Alternatively you could use the modern scroll and load more data in each column. You preload 5-10 users in the online users box, then when the user's scroll offset is almost at the bottom, load 5-10 more.

I can understand why you're saying it could be a performance issue, but it doesn't necessarily have to be one with the correct approach