Hibernate, C3P0, Mysql — Broken Pipe

Question

MySQL seems to have an 8 hour time out on its connections. I\'m running multiple WARs in Tomcat utilizing Hibernate for ORM. After 8 hours (i.e. overnight), I get broken pip

Answer 1

This is a solution when you have a broken pipe because of combination of tomcat's wait_timeout=28800 sec(8h) and maxIdleTime=0 in c3p0:

I've changed the local tomcat wait_timeout via my.ini file to 120sec (2 min). And I placed the following:
maxIdleTime=100
idleConnectionTestPeriod=0 (same as default/as if it didn't exist)
other:
acquireIncrement=2
minPoolSize=2
maxPoolSize=5
maxIdleTimeExcessConnections=10

I had no problems with this setup.

I didn't need to use idleConnectionTestPeriod!

If tomcat's wait_timeout is 28800 sec, and maxIdleTime is 25200, it means that c3p0 will close the idle connection in 3600sec (1h) earlier, before tomcat throws a "broken pipe" exception. Isn't that right?!

As you can see I have no issues with providing only maxIdleTime.

Unfortunately, these:
maxIdleTime
idleConnectionTestPeriod
configuring_connection_testing
testConnectionOnCheckin
don't explain too much the corner cases.

And, btw, here is how to open the tomcat's my.ini file with Notepad++: http://drupal.org/node/32715#comment-4907440

Cheers,
Despot