I'm having trouble with a Rails application on Heroku. The number of requests per minute it can handle has suddenly dropped SHARPLY.
I'm looking for a list of things to investigate for how to fix this, as we're releasing today and everything I've checked can't seem to increase this performance cap.
Specifically, my setup is: Heroku, Unicorn and Rails with a MongoHQ database.
Results 2 days ago: 40,000 requests per minute Results now: 2,000 requests per minute
I've tried the following steps to bring performance back up to previous levels, but none of them have made a difference and I'm stumped: - increase the number of dynos - swap to 2x dynos - roll back to the previous codebase and config files - disable Paper Trail logging - look for Heroku errors in the error logs - look for swapping or a large index in mongoHQ - check memory usage -- seems fine - check/adjust Unicorn settings -- more workers, shorter backlogs
The only change in requests per minute I've had success with is, lowering the dynos below 4 decreases the requests per minute.
What else haven't I checked?