Exception in thread "com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2" java.lang.OutOfMemoryError: PermGen space
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at com.mchange.v2.c3p0.impl.C3P0ImplUtils.supportsMethod(C3P0ImplUtils.java:309)
at com.mchange.v2.c3p0.impl.NewPooledConnection.<init>(NewPooledConnection.java:101)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:198)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Exception in thread "com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0" java.lang.OutOfMemoryError: PermGen space
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at com.mchange.v2.c3p0.impl.C3P0ImplUtils.supportsMethod(C3P0ImplUtils.java:309)
at com.mchange.v2.c3p0.impl.NewPooledConnection.<init>(NewPooledConnection.java:101)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:198)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
如上，是tomcat报出的溢出错误代码
------解决方案--------------------------------------------------------
楼上的没有一个说对了的。。。
java.lang.OutOfMemoryError: PermGen space
PermGen space的全称是Permanent Generation space，是指内存的永久保存区域。
用 -Xms512m -Xmx1024m 是不能增大永久保存区的。
永久区内存溢出，一般三种原因：
1、确实jar包太大，因为所有类定义都是装载入PermGen，所以jar包太多太大溢出了；
2、热部署次数过多，或者动态调试啥的，其实本质原因类似1；
3、程序写的搓，滥用static，导致溢出。
解决方案也是对应的三种：
1、调大PermGen： -XX:MaxPermSize=256m
2、重启中间件，或者调大PermGen；
3、修改程序消灭Bug，或者缓存用外部MemCache等。
参见：
http://www.webspherechina.net/home/space.php?uid=35096&do=blog&id=53771
http://www.cnblogs.com/feisky/archive/2010/07/23/1783780