Preventing Mongrel/Mysql Errno::EPIPE exceptions

rubyonrails-talk
1

I have a rails app serving up XML on an infrequent basis. This is being run with mongrel and mysql. I've found that if the app does not get exercised for longer than a few hours it goes dead ("Lost Connection to MySQL") and starts throwing Errno::EPIPE errors. It seems that the mysql connection gets timed out for inactivity or something like that.

It can be restarted with 'mongrel_rails restart -P /path/to/the/mongrel.pid' ... but that's not really a solution. My collaborator expects the app to be there when he is working on his part (and I am most likely not around).

My question is:

What can I do to prevent this problem from occurring in the 1st place? (e.g. don't time me out!!).

Failing that, is there some code I can insert somewhere to automatically remake the Db connection?

-- Mike Berrow

2

My question is:

What can I do to prevent this problem from occurring in the 1st place? (e.g. don't time me out!!).

Failing that, is there some code I can insert somewhere to automatically remake the Db connection?

change the value of config.active_record.verification_timeout to something below whatever timeout your mysql timeout is set to.

Fred

3

Frederick Cheung wrote:

change the value of config.active_record.verification_timeout to something below whatever timeout your mysql timeout is set to.

It was also suggested elsewhere

that I do the following: (full advice is at https://boxpanel.blueboxgrp.com/public/the_vault/index.php/Mongrel_/_MySQL_Timeout )

# Set the verification timeout so that the mongrel connection won't die if left alone (1 week) ActiveRecord::Base.verification_timeout = 604800

# Keep Connection Open Thread.new {   loop {     ActiveRecord::Base.verify_active_connections!;     1800.times { sleep 2 }   } }.priority = -10

and also (in mysql.cnf) # Fix for bug where mongrel doesn't close timed-out connections: Just don't time out connections. wait_timeout= 3456000

Why is that thread calling verify_active_connections! needed if verification_timeout < wait_timeout ? -- Mike Berrow