There is no specific recommendation for scaling FreeSWITCH this is because single setting changes can cause an order of magnitude or more differences in concurrent call handing capabilities on the same exact hardware and software builds.

You will have to test your specific deployment scenarios directly.

Example, a box running G.711 to  G.711 calls is simply proxying media and may easily handle 1000 calls, however make those G729 to G711 calls and that number may be cut in half to 500 calls, now change that to OPUS Stereo  32K to G.729 may only do 10% of that capacity due to the additional load handling required to decode opus to SLIN, then resample it to 8K and mux the 2 stereo channels down to 1 channel, then recompress it all the way down to G.729. And we havent even talked about voicemail, conferencing/3way calling, etc etc etc etc etc etc

From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org> On Behalf Of Praveenkumar T
Sent: Thursday, February 18, 2021 8:41 AM
To: freeswitch-users@lists.freeswitch.org
Subject: [Freeswitch-users] Hardware Specification and Performance

Dear,

I have been going through the below link and It would be helpful if you could let me know the below two points.

https://freeswitch.org/confluence/display/FREESWITCH/Specifications

1. like to know more about the maximum concurrent call the free switch can support with the recommended system requirement.
2. Does it need any upgrade in the system hardware requirements/additional packages if one tries to bring SBC before the Freeswitch in case of external SIP trunk configuration.  

Thanks & Regards

Praveen