Who and how do you determine 'Top 20' users for a specific day? As with any feature, its a trade off.
I said it earlier in this thread: Amount of posts, and amount of likes/points (influence).
Did you have your member list visible?
Yep. But when 1.2 is out, I'm switching from memberlist, to "top users" (1.2 style you see now).
Were you getting exorbitant views to profiles coming from it? Did it cause you plenty of resources?
Out of nowhere, more and more spammers are registering to my site, and more and more are viewing the profiles, meaning that spammers found bad links in my members' profiles. I've been proactively banning these spammers, and getting rid of the link spam so that it goes back to normal.
For 5,000 members, 8,000 posts, 3,000 threads, I shouldn't have 1 gig being used. But
it is eating up that much.
You said it yourself, there's a small number of people who may use it, so you wouldn't kill resources by making a simple query. If you nofollow it, spiders should ignore it and further reduce the queries.
It may be a simple query, you're forgetting that you're loading 1 more for each member that you load.
See it this way. Even cached:
Search for birthday:
20 users = 20 queries
Click "view more" you add 20 more, right? That's 40 thus far. If you keep going, 60, 80, 100, 120, etc.
Every time you're fetching, you're adding 20 each time.
Like I said, a small number only use it - when I said this, I meant
your members (and/or real visitors). Not spammers. Not bots. This trade-off is bad, because you're just wasting queries.