Rails - Issue with passenger and mysql

Question

My Rails app currently runs on Passenger. We have six machines in production with each machine having 45 instances of passenger. Each instance of Passenger seems to be having a open connection with MySQL. So there are about 270 open connections with MySQL.

A few minutes after the application is started MySQL seems to at 400% CPU and the application almost becomes non-responsive with a lot of pending requests in the global queue.

Prior to this release the application was running on Mongrel (six machines with each machine running 5 instances of mongrel). We did not see any issues there.

Will reducing the number of Passenger instances solve the issue? Is there a way we can have a connection pool for the passenger instances (Instead of each instance having a separate connection).

Thanks,
Sivakumar

What kind of machines are you running on? Are they VPS'? RAM? CPU? — lebreeze, Mar 24 '11 at 08:23
I meant to ask: How much RAM? How fast are the CPUs? How many cores etc... — lebreeze, Mar 24 '11 at 09:04
Much probably. Each Passenger instance spawns multiple workers, are you counting those in? I think the best approach is one passenger instance (spawn sever) and to configure it with one worker for each core (it may vary a little). — Henry Mazza, Jul 09 '11 at 20:53

score 0 · Answer 1 · edited May 23 '17 at 12:14

0

Passenger shares db connections among all processes. Make sure your database.yml has a high pool size.

passenger-hosted-rails-app-painfully

edited May 23 '17 at 12:14

Community

1
1

answered Jul 22 '11 at 09:21

Horacio

2,727
5
26
29

For posterity's sake, I want to note that this may not be true. See [this post](https://groups.google.com/forum/#!topic/phusion-passenger/hfdeaysTqPo). – twelve17 Apr 08 '14 at 12:09

Rails - Issue with passenger and mysql

1 Answers1