I tried both Arrowchat and Cometchat and had the same problem with both, the server load created slowed page load speeds by about 150%. It went from 1-3 seconds to 4-9 seconds per page load.
In both cases I used the "push" service, but that seems to make almost no difference.
My forum is medium size, we have about 700 users online at any give time, peaking at about 900 with about 150-200 being logged in members.
I set up Arrowchat so only logged in members would appear in the chat list and had 5 mins before they were marked as inactive.
My site is a marketplace, so this is used by buyers to contact sellers quickly. I can't lower idle time to less than 5 mins otherwise sellers would appear offline constantly.
I need someone that can help set this up for me, possibly make customization to optimize it so server load is minimum.
Does anyone have this running on a larger or medium size Vbulletin site? It seems unless I turn off most of the features, this is unusable for larger scale sites.