Hi, I would like to put 500 - 1000 calls into a FS system. I have a Dell R900 server with these properties: 8 processors at 2.40GHz 8GB RAM Gigabit ethernet I use sipp to send RTP streams. I use the FS settings recommended here: https://wiki.freeswitch.org/wiki/Performance_testing_and_configurations including the in-memory core.db. I also have used the "-rp" and "-nosql" settings on the FS command-line, and also used the "chrt" command to increase the priority to real-time. In all cases, at around 300 concurrent calls, the RTP inter-packet delay becomes unacceptably high. The voice quality is severely impacted. During the test, the CPU is not overloaded. It is using only about 1.5 of the 8 processors. Are these results expected? Has anyone gone higher than 300 concurrent calls? Is there anything else that I can do with configuration to improve throughput? Thanks, David