also, I just noticed that the same user/session increases the views on a forum post every time they view it. seems like that is a bit iffy behavior. I am guessing you are doing a simple INCR. One way I have gotten around this was to store a SET of sessions on each object that needs counted, length is then still an O(1) cost IIRC. Alternatively you can get crafty with lua and store the list of read posts in the session (and clear it).

also, what are you using for fallback? long polling? (socket.io etc)

I am really liking these forums, and it would integrate nicely with several of my current nodejs projects. However, I have a few questions which may tilt me either into supporting it or whipping out my own super-simple one, this mostly comes down to storage situation.

Great choice with redis from a performance angle, but without knowledge of exactly how you store things in it, I am moderately concerned with overhead. Any rough estimates on storage overhead per user/post/etc (any specs would be helpful). I run a custom fork of redis to do geocoding, so downgrading to one that supports virtual memory is not-doable. This means I would need the forums, my nodejs site, and possibly mongodb with its big memory mapped files to all fit within 2GB of ram. I am using both ramnode and digitalocean SSD backed boxes for hosting. This information would help me make a decision as to viability.

Also, where/how are you storing images? Are these being serialized into redis, or are they being stored onto disk? Whereas I can no doubt store a shit-ton of text within a reasonable amount of ram, I could easily see thumbnails or user uploads getting out of hand. Any information there would be more then helpful.

Finally, do you have anything to shard on, or am I going to have to figure out something else in that regard?

Thanks
Richard Cesar