2 ms·
These test results are surprising. In my experience, when the server cpu is pegged, it causes latency to shoot through the roof unless the number of parallel re
by ec109685 4y ago
These test results are surprising. In my experience, when the server cpu is pegged, it causes latency to shoot through the roof unless the number of parallel requests is finely tuned.
In this case, there are max 50 workers hitting the server, so you’d expect 50 parallel requests to be outstanding at once. 1300 req/sec with 50 workers, would be 26 msec/req, which matched the results.
So I wonder why the server being pegged didn’t affect things more? Super curious what the server side metrics were during the test.
- ec109685 4y agoI guess one explanation is that given the load test isn’t sending constant traffic but each virtual user instead waits for each request before sending the next one, it naturally starts throttling. Constant Load, which k6 supports, can help pinpoint the server’s breaking point.
- zer0tonin 4y agoYes this is a valid point. I didn't think of using constant load at the time of writing the article.