Heroku Postgres: This connection has been closed

Question

I developed a small Heroku + Grails + Postreg application. It would work fine somewhat 20 minutes after deployment, after that I always get:

 This connection         


        

Answer 1

A combination of @Macchiatow's answer and @Jonik's comment, this is what I used to work, with fewer properties:

dataSource {
    pooled = true
    properties {
        testOnBorrow = true
        testWhileIdle = true
        testOnReturn = true
        validationQuery = "SELECT 1"
    }
    driverClassName = "org.postgresql.Driver"
    dialect = "..."
}

Answer 2

I have resolved it myself by adding this to DataSource.groovy:

dataSource {
    pooled = true
    properties {
       maxActive = -1
       minEvictableIdleTimeMillis=1800000
       timeBetweenEvictionRunsMillis=1800000
       numTestsPerEvictionRun=3
       testOnBorrow=true
       testWhileIdle=true
       testOnReturn=true
       validationQuery="SELECT 1"
    }
}