Can anyone clarify why we are hitting 401 Unauthorized errors on WebSocket connections when ramping up concurrent users in our JMeter script? We are testing the Genesys Cloud platform API throughput for real-time call monitoring. The setup uses a standard JMeter thread group with 200 concurrent virtual users connecting via the WebSocket endpoint /v2/websocket. Initially, connections establish fine, but as we hit the 150-user mark, we start seeing a steady stream of 401s on the auth handshake phase. The OAuth tokens are valid and refreshed every 5 minutes via a separate thread, so token expiry seems unlikely.
We are running this from our Singapore office, connecting to the us-east-2 region. The JMeter config uses a simple CSV data set for user credentials and a WebSocket sampler with a keep-alive policy. Is there a specific rate limit or connection cap for WebSocket handshakes that we are hitting? We haven’t seen this in our documentation for the platform_api. Any insights on how to tune the JMeter script or if this is a known platform constraint for high-concurrency load tests would be appreciated.