Why does this setting… trigger immediate 408 Request Timeout errors when concurrent SIP INVITE volume exceeds 50 calls per second?
Running JMeter 5.6 with a custom SIP plugin to validate trunk capacity on US1. The goal is to determine the maximum sustainable call rate before Genesys Cloud drops connections. The test uses a constant throughput timer to ramp up to 60 TPS. The JMeter config targets the public SIP URI provided for the trunk. All credentials are correct, and the trunk is active.
The error occurs consistently after 10 seconds of steady load. The response from the Genesys Cloud SIP proxy is a 408. This suggests the system is rejecting new INVITEs due to resource exhaustion or rate limiting, but the documentation does not specify a hard cap for SIP INVITE rates per trunk.
SIP/2.0 408 Request Timeout\nVia: SIP/2.0/TCP 192.168.1.100:5060;branch=z9hG4bK...\nTo: <sip:[email protected]>\nFrom: <sip:[email protected]>\nCall-ID: 12345-6789@192.168.1.100
The environment is US1. The trunk is configured with standard settings. No custom codecs are applied. The issue persists across multiple test runs. Is there a configuration parameter to increase the SIP INVITE acceptance rate? Or is this a known limitation for standard trunks?
Need to understand if this is a hard limit or if it can be adjusted. The current throughput is insufficient for the target volume of 200 concurrent calls. Any guidance on tuning the SIP stack or adjusting JMeter parameters to avoid this timeout would be helpful. The logs show no authentication errors. The connection is established, but the INVITE is not processed. This behavior is consistent with rate limiting, but no 429 is returned. Instead, the 408 indicates a timeout waiting for a response. This suggests the server is overloaded or dropping packets. Clarification on the expected behavior and any workarounds is requested.