Greetings, I'm working on a server in an SBC setup. It has a copper 10/100 for admin and 2 GiGe connections for private/public peering(SIP signaling and media). I've been testing with some traffic and am finding I hit a ceiling around 800-900 active calls. The system CPU ends up being about 40% which seemed really high to me. Is this simply due to the amount of networking happening with the rtp in and out the different interfaces or am I operating something in a non optimized fasion ? It's an e1000 based card, I've tried messing around with the interrupt throttling but in the end the dynamic setting seemed to work best. Given that a chassis has done 3k simultaneous calls with about half the processing power I currently have in this server I must be running sub optimal. Any idea's of where I might look to correct this ? kernel tuning ? network tuning ? Other than seeing a lot of irq's from the network cards I"m not sure what else might be using up the system cpu. To squeeze out as much as possible I have the core databases housed in a tmpfs partiion, and I've also disabled the sql scoreboard (-nosql). Any other areas I should be exploring to increase the number of calls this chassis can process ? Thanks in advance for any ideas -Eric