Hi all --
We have created a fairly massive shiny app that is used in real time during motorsports racing events. It receives real time GPS/telemetry data from vehicles on track and allows users to compare driving lines and other aspects between different laps and/or vehicles/competitors.
We have a professional subscription to shinyapps.io to test out its viability for hosting the app long term. We have the app configured to use the xxxlarge app size, spin up 10 instances, and we limit each instance to only 1 worker process and 1 connection (the resources required for this app are high, and any time we have a setup that allows sharing of resources, there are performance hits).
However, at random times, we receive 503 errors when the app attempts to refresh data, or when a user first attempts to visit the app. It usually requires clearing their browser cache in order to get the 503 error to go away (otherwise, once they get the 503, they are never able to get into the app until browser cache is cleared).
I'm not sure why we are receiving the 503 errors as often/sporadically as we do. There doesn't seem to be a pattern, it's very random.
Has anyone else experienced this behavior on shinyapps.io?