Czytam wgląd w to, w jaki sposób mogę skonfigurować aplikację play 2.0, aby nie korzystała z tak wielu połączeń z bazami danych zarówno w trakcie ewolucji bazy danych, jak iw czasie wykonywania. Zadałem to w grupie i na IRC bez powodzenia.

Używam instancji cleardb ignite (max_user_connections = 10) z heroku ...

Zasadniczo, gdy próbuję uruchomić ewolucję bazy danych w mojej aplikacji play 2.0, otrzymuję:

<code>! @6a2mjd7kg - Internal server error, for request [GET /] ->

play.api.db.evolutions.InvalidDatabaseRevision: Database 'default' needs evolution! [An SQL script need to be run on your database.]
at play.api.db.evolutions.EvolutionsPlugin$$anonfun$onStart$1.apply(Evolutions.scala:424) ~[play_2.9.1.jar:2.0]
at play.api.db.evolutions.EvolutionsPlugin$$anonfun$onStart$1.apply(Evolutions.scala:410) ~[play_2.9.1.jar:2.0]
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) ~[scala-library.jar:0.11.2]
at scala.collection.immutable.List.foreach(List.scala:45) ~[scala-library.jar:0.11.2]
at play.api.db.evolutions.EvolutionsPlugin.onStart(Evolutions.scala:410) ~[play_2.9.1.jar:2.0]
at play.api.Play$$anonfun$start$1.apply(Play.scala:60) ~[play_2.9.1.jar:2.0]
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 10. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 9. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 8. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 7. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 6. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 5. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 4. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 3. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 2. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 1. Exception: null
 [error] application - 

! Internal server error, for request [GET /@evolutions/apply/default?redirect=http%3A%2F%2Flocalhost%3A9000%2F] ->

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: User '52841e548f150d' has exceeded the 'max_user_connections' resource (current value: 10)
at sun.reflect.GeneratedConstructorAccessor26.newInstance(Unknown Source) ~[na:na]
at       sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.  java:27) ~[na:1.6.0_29]
at java.lang.reflect.Constructor.newInstance(Constructor.java:513) ~[na:1.6.0_29]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) ~[mysql-connector-java-  5.1.18.jar:na]
at com.mysql.jdbc.Util.getInstance(Util.java:386) ~[mysql-connector-java-5.1.18.jar:na]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1052) ~[mysql-connector-java-5.1.18.jar:na]
</code>

Wtedy też często otrzymuję zwykłe „Przekroczone max_user_connections”, co zdarza się bardzo często, gdy nie robię ewolucji.

Mogę również otrzymać ten komunikat o błędzie:

<code>com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: User '52841e548f150d' has exceeded the 'max_user_connections' resource (current value: 10)
at sun.reflect.GeneratedConstructorAccessor19.newInstance(Unknown Source) ~[na:na]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) ~[na:1.6.0_29]
at java.lang.reflect.Constructor.newInstance(Constructor.java:513) ~[na:1.6.0_29]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) ~[mysql-connector-java-5.1.18.jar:na]
at com.mysql.jdbc.Util.getInstance(Util.java:386) ~[mysql-connector-java-5.1.18.jar:na]
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1052) ~[mysql-connector-java-5.1.18.jar:na]
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 10. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 9. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 8. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 7. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 6. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 5. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 4. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 3. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 2. Exception: null
[error] c.j.b.h.AbstractConnectionHook - Failed to acquire connection Sleeping for 1000ms and trying again. Attempts left: 1. Exception: null
[error] application -
</code>

Mój application.conf wygląda tak i wypróbowałem wiele odmian ...

<code>db.default=mysql 
db.default.driver=com.mysql.jdbc.Driver
db.default.url="mysql://usr:pass@db_url.com/db_name"
db.default.minSize=1
db.default.maxSize=2
</code>

Wszelkie wskazówki, sugestie, linki byłyby w tym momencie niezwykle pomocne ...