Incorrect app concurrency metrics affecting Fly Proxy scaling

[mayailurus]

@tjhorner

Here it is: transit-tracker-api/fly.toml at main · tjhorner/transit-tracker-api · GitHub

[http_service.concurrency]
  type = "requests"
  soft_limit = 35

Thanks for the details… You want type = "connections" for WebSockets, actually. (And also fly_app_concurrency was showing request count earlier, as I understand it.)

@wjordan

Worth mentioning the type option (which it looks like you already discovered), which defaults to connections, but can be set to requests for the http handler. The app’s concurrency (reported by the fly_app_concurrency metric and the ‘VM Service Concurrency’ graph on the Metrics tab of the Dashboard) will be based on either connections or requests based on this setting.

"requests" usually is the best choice, but…