Bug 160370

Summary: "Automatic User Information Look Up" can cause lag and excess flood
Product: [Applications] konversation Reporter: Lorenzo J. Lucchini <ljlbox>
Component: generalAssignee: Konversation Developers <konversation-devel>
Status: RESOLVED FIXED    
Severity: normal    
Priority: NOR    
Version: 1.0.1   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Lorenzo J. Lucchini 2008-04-04 17:35:04 UTC 
Version:           1.0.1 (using KDE 3.5.9)
Installed from:    Ubuntu Packages
OS:                Linux

The "Enable Automatic User Information Look Up" feature (in Configure Konversation / Behavior / Chat Window) is selected by default.

While, by default, it attempts to avoid excessively long /WHO responses, by having "Max number of users in a channel" set to 200, it still seems to create serious problems when several smaller channels are joined.

The /WHO requests apparently cause severe lag (and practically continuous lag, if "Update Interval" is set too low, such as the default 90 seconds), and if enough channels are joined, an "Excess Flood" quit by the network is inevitable.

This is particularly serious as the client reconnects automatically and rejoins the channels it was in, since it can result in a never-ending row of excess floods if the user is not at the terminal when the problem becomes visible.
Comment 1 Eike Hein 2008-04-04 17:38:36 UTC 
SVN solves the flooding problems with a rewritten outbound queue scheduling system that is smart enough to reorder outbound traffic to reduce interactive latency while aggressively throttling the rate.