Outbound dialer api rate limit 429 on bulk campaign update

could someone explain why i get 429 too many requests when hitting /api/v2/outbound/campaigns with jmeter. running 50 concurrent threads to update status on 10k campaigns. env is gc prod us-east-1. thought the limit was higher for admin users?

1. Implement exponential backoff in the JMeter script. The 429 response includes Retry-After headers.
2. Parse that header and pause the thread accordingly.
3. Consider batching updates to 50-100 campaigns per request instead of individual calls.
   This approach respects the API limits and prevents throttling during bulk operations.

The problem here is the lack of client-side throttling logic in the JMeter test plan. The suggestion above regarding Retry-After headers is correct, but manual parsing is fragile. For IaC deployments or bulk updates, automated backoff is standard practice.

Use a JSR223 PostProcessor in JMeter to handle the 429 response automatically. This script extracts the Retry-After value and pauses the thread.

if (prev.getResponseCode() == "429") {
 def retryAfter = prev.getResponseHeader("Retry-After")
 def waitTime = (retryAfter ? retryAfter.toInteger() * 1000 : 5000)
 Thread.sleep(waitTime)
 prev.setResponseCode("200")
 prev.setSuccessful(true)
}

Environment requirements for this approach:

Batching is still recommended. Updating 10k campaigns individually is inefficient. Group updates by status or campaign ID where possible. The API documentation for outbound suggests max batch sizes of 100. Adjust the CSV Data Set Config to feed batches. This reduces total request count significantly.