How much simultaneous calls WCS supports for G.729, G.711, Opus codecs?

Main hardware resource for WCS3 is CPU.

Please see results of our CPU performance tests below.
The testing was performing on Corei7, 4 cores, 2.66 GHz dedicated server, 1GBps link.

WebRTC to Bria call with g.729 encoding utilizes about 0.6% of overall 4 core CPU.

WebRTC to WebRTC call with Opus utilizes the same percent of the CPU time.
Here we see difference in performance about 2 times. Because in the first case 1 WebRTC client is in “talking” state.
But in the second non-transcoding case we have 2 WebRTC clients in “talking” state.
This means g.729 trancoding utilizes 2 times greater CPU resources than the Opus non-transcoded call.

You can perform your own tests with your equipment and predict CPU utilization for 10, 100 etc simultaneous calls.

Recommended hardware:
Latest or pre-latest Xeons servers. High CPU performance (GHz, number of cores, number of threads).
Memory and disk space is not critical, but should be fast enough.