Marco created DERBY-7049:
----------------------------
Summary: OutOfMemoryError: Compressed class space
Key: DERBY-7049
URL: https://issues.apache.org/jira/browse/DERBY-7049
Project: Derby
Issue Type: Bug
Reporter: Marco
After a few days of working with an embedded Derby database (currently version
10.13.1.1), the following error occurs:
*java.lang.OutOfMemoryError: Compressed class space*
{code:java}
java.lang.OutOfMemoryError: Compressed class space
at java.lang.ClassLoader.defineClass1(Native Method) ~[na:1.8.0_201]
at java.lang.ClassLoader.defineClass(ClassLoader.java:763) ~[na:1.8.0_201]
at java.lang.ClassLoader.defineClass(ClassLoader.java:642) ~[na:1.8.0_201]
at
org.apache.derby.impl.services.reflect.ReflectLoaderJava2.loadGeneratedClass(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at
org.apache.derby.impl.services.reflect.ReflectClassesJava2.loadGeneratedClassFromData(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at
org.apache.derby.impl.services.reflect.DatabaseClasses.loadGeneratedClass(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.services.bytecode.GClass.getGeneratedClass(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at
org.apache.derby.impl.sql.compile.ExpressionClassBuilder.getGeneratedClass(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.sql.compile.StatementNode.generate(Unknown Source)
~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.sql.GenericStatement.prepMinion(Unknown Source)
~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.sql.GenericStatement.prepare(Unknown Source)
~[derby-10.13.1.1.jar:na]
at
org.apache.derby.impl.sql.conn.GenericLanguageConnectionContext.prepareInternalStatement(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.jdbc.EmbedPreparedStatement.<init>(Unknown Source)
~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.jdbc.EmbedPreparedStatement42.<init>(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at org.apache.derby.jdbc.Driver42.newEmbedPreparedStatement(Unknown Source)
~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.jdbc.EmbedConnection.prepareStatement(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at org.apache.derby.impl.jdbc.EmbedConnection.prepareStatement(Unknown
Source) ~[derby-10.13.1.1.jar:na]
at
org.datanucleus.store.rdbms.datasource.dbcp.DelegatingConnection.prepareStatement(DelegatingConnection.java:259)
~[datanucleus-rdbms-4.0.12.jar:na]{code}
I tried to solve the problem by periodically shutting down the database,
because I read that the generated classes as well as all other allocated
resources should be released when the DB is shut-down.
I thus perform the following code once per roughly 20 minutes:
{code:java}
String shutdownConnectionURL = connectionURL + ";shutdown=true";
try {
DriverManager.getConnection(shutdownConnectionURL);
} catch (SQLException e) {
int errorCode = e.getErrorCode();
if (DERBY_ERROR_CODE_SHUTDOWN_DATABASE_SUCCESSFULLY != errorCode &&
DERBY_ERROR_CODE_SHUTDOWN_DATABASE_WAS_NOT_RUNNING != errorCode) {
throw new RuntimeException(e);
}
}
{code}
Unfortunately, this has no effect :( The OutOfMemoryError still occurs after
about 2 days. Do I assume correctly that the above code _should_ properly
shut-down the database? And do I assume correctly that this shut-down should
release the generated classes?
IMHO, it is already a bug in Derby that I need to shut-down the database at all
in order to prevent it from piling up generated classes. Shouldn't it already
release the generated classes at the end of each transaction? But even if I
really have to shut-down the DB, it is certainly a bug that the classes are
still kept in "compressed class space" even after the shut-down.
I searched the release notes and the existing bugs (here in JIRA) and did not
find anything related to this OutOfMemoryException. Hence, I open this
bug-report, now.
This issue was originally reported in
[subshare#74|[https://github.com/subshare/subshare/issues/74],] but it is IMHO
clearly a Derby bug.
--
This message was sent by Atlassian JIRA
(v7.6.14#76016)
