> Could these 500 connections/second cause (on average) 2600Mb memory usage > per 2 second ~ 1300Mb/second. > or For 1 connection around 2-3Mb.
In terms of garbage generated it's much less about number of connections as it is about what you're doing with them. Are you for example requesting large amounts of data? Large or many columns (or both), etc. Essentially all "working" data that your request touches is allocated on the heap and contributes to allocation rate and ParNew frequency. -- / Peter Schuller (@scode, http://worldmodscode.wordpress.com)