[SR-Users] Memory allocation

Greetings, I have some things that i want to udnerstand about Kamailio's memory allocation. My settings are 1024Mb for shared memory and 12Mb for private memory. I'm running Kamailio on a machine with CentOS7 and 2Gb of RAM. As i understand, at startup Kamailio will allocate 1024+12*number_of_processes megabytes of memory. Is this correct? When i set up Kamailio to run with 150 processes, after starting, i still have 500Mb of free RAM and therefore not allocated to any process. That goes against what i wrote earlier. What is the best way to plan for memory specs in my machines according to the desired number of processes and shared\private memory defined? Best Regards, Duarte Rocha