Anyone free to help troubleshoot this WebRTC signaling failure during load testing.
Running JMeter 5.6.2 from Singapore. Targeting the Genesys Cloud WebRTC softphone endpoints. Ramp up to 200 concurrent threads. Single thread works fine. At 200 threads, get 412 Precondition Failed on POST /api/v2/communications/calls. The SDP offer generated by the client seems valid, but the server rejects it.
Error response body shows:
{
“code”: “preconditionFailed”,
“message”: “Invalid SDP offer”
}
Checked the SDP payload in JMeter. Looks standard. Codec list includes opus, pcma, pcmu. No obvious issues. Lowering threads to 50 works perfectly. Scaling back up to 200 triggers the 412 again.
Is there a hidden rate limit on WebRTC signaling? Or does the platform drop SDP validation under high load? Sharing JMeter config if needed. Looking for workarounds or known limits.