We just added two new panels to https://fly-metrics.net dashboards:
fly-proxy error count
This metric is incremented when our edge proxy sends an error message to your app’s logs. It doesn’t immediately tell you what the issue is (it could be on your end or it could be on Fly’s end).
If this shows an unexpected increase, you should check your logs to see what the actual error messages are.
instance soft/hard limits reached
These counters gets incremented when an instance reaches the concurrency limits configured on your app.
Assuming you’ve configured the limits appropriately (based on how many requests one instance of your app can handle at the same time):
- if all instances of your app are hitting the soft limit a lot, you probably need to add more instances soon.
- if all instances of your app are hitting the hard limit a lot, you likely need to add more instances - connections may be rejected if no other instances are under the hard limit.