Trying to understand the exact threshold for WebSocket connection resets within Architect flows when subjected to aggressive JMeter load testing. The environment is Genesys Cloud (Singapore region), using the Python SDK 2.1.0 for initial token generation, followed by a custom JMeter script simulating 200 concurrent agents logging into a softphone client. The Architect flow is a simple IVR menu with two voice prompts and one digit collection node. During the ramp-up phase, specifically when the concurrent user count hits 150, the WebSocket connections start dropping with a 429 Too Many Requests error instead of a clean 101 Switching Protocols handshake. The JMeter config uses a constant throughput timer set to 50 requests per second, with a 500ms delay between reconnection attempts. The error logs show the 429s originating from the /api/v2/conversations/calls endpoint, suggesting the platform is throttling the initial media negotiation before the call is even established. This is unexpected because the documentation states that WebSocket connections are not subject to the standard REST API rate limits of 100 requests per minute. The load test is designed to mimic a shift change scenario where agents log in simultaneously. The Python SDK handles the OAuth2 token refresh correctly, so the issue is not authentication-related. The JMeter threads are configured to retry the connection three times before marking the transaction as failed. The failure rate increases to 40% when the concurrency reaches 200 users. The goal is to determine if this is a platform-side limitation for the Singapore region or a misconfiguration in the JMeter script. The Architect flow itself is lightweight, with no external API calls or complex routing logic. The error persists even when reducing the concurrent users to 100, though the frequency decreases. The WebSocket keep-alive interval is set to the default 30 seconds. Any insights into how to properly tune the JMeter script to avoid triggering these 429s during high-concurrency login simulations would be appreciated. Is there a specific header or parameter that needs to be adjusted in the WebSocket upgrade request to bypass this throttling behavior?
TL;DR: Rate limits on WebSocket reconnects are often misdiagnosed. The 429 usually stems from token refresh storms or aggressive retry loops in your client script, not the Architect flow itself.
Make sure you are distinguishing between the Architect flow execution limit and the underlying WebSocket connection rate limit. When simulating 200 concurrent agents, the Python SDK or your custom client likely triggers a token refresh or reconnection attempt for every single agent simultaneously. Genesys Cloud enforces strict rate limits on these handshake events to protect the signaling infrastructure.
The solution involves implementing exponential backoff with jitter in your JMeter script. Instead of immediate retries on a 429, introduce a randomized delay. Here is a simple logic snippet for your Python pre-processor or JMeter BeanShell:
import time
import random
def handle_reconnect(attempt):
# Exponential backoff: 1s, 2s, 4s...
base_delay = 2 ** attempt
# Add jitter to prevent thundering herd
jitter = random.uniform(0, 1)
total_delay = base_delay + jitter
print(f"Retrying in {total_delay:.2f} seconds...")
time.sleep(total_delay)
return attempt + 1
Also, verify that your JMeter thread group is using a “Ramp-Up” period that is significantly longer than the expected connection time. A sudden spike of 200 connections will definitely hit the limit. Spread the load over at least 60-120 seconds.
From a WFM perspective, I see similar patterns when agents try to log in simultaneously at shift start times. The system handles it, but the API calls get throttled if they are not staggered. Your test script needs to mimic real-world behavior, which includes slight delays and retries, not instantaneous bursts.
Check the Retry-After header in the 429 response. It tells you exactly how long to wait. Ignoring it causes the client to get blocked for longer periods. Implementing this header respect in your test script will give you a much more accurate representation of system stability under load.