Java(TM) SE Runtime Environment (build 1.6.0_03-b05)
BEA JRockit(R) (build R27.5.0-110_o-99226-1.6.0_03-20080528-1505-linux-x86_64, compiled mode)
c3p0版本0.9.1，0.9.1.2在高并发时，测试2000并发出现线程阻塞，resin服务挂起，dump线程出现
"com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0" id=85 BLOCKED
waiting on com.mchange.v2.resourcepool.BasicResourcePool@33479e3
at com.mchange.v2.resourcepool.BasicResourcePool$1RefurbishCheckinResourceTask.run (BasicResourcePool.java:1229)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run (ThreadPoolAsynchronousRunner.java:547)
"com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1" id=86 BLOCKED
waiting on com.mysql.jdbc.JDBC4ResultSet@eaa775
owned by "com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2"
at com.mysql.jdbc.ResultSetImpl.realClose (ResultSetImpl.java:7478)
c3p0作者也说了
https://github.com/swaldman/c3p0/issues/10
this looks very similar to a deadlock reported on SourceForge here. It's fixed already in the latest snapshot release of c3p0-0.9.5-pre3. give that a shot if you can (and let me know how it goes!). if not, c3p0-0.9.5-pre3 (non-SNAPSHOT) will be published very shortly. i may backport this fix to the stable 0.9.2 series, but not until people have kicked around 0.9.5-pre3 for a while. as an aside, it looks like you have not set a preferredTestQuery or automaticTestTable, and so are using the default DatabaseMetaData.getTables(...) Connection test. That's slow; I strongly suggest defining a preferredTestQuery. good luck!
换用dbcp 1.4版本没出现问题，配置如下
oscache2.4.1在高并发时也会出现线程阻塞，resin服务挂起
-- Waiting for notification on: com/opensymphony/oscache/base/EntryUpdateState@0x48702240[fat lock]
at jrockit/vm/Threads.waitForNotifySignal(JLjava/lang/Object;)Z(Native Method)
at java/lang/Object.wait(J)V(Native Method)
at java/lang/Object.wait(Object.java:485)
at com/opensymphony/oscache/base/Cache.getFromCache(Cache.java:278)
^-- Lock released while waiting: com/opensymphony/oscache/base/EntryUpdateState@0x48702240[fat lock]
at com/opensymphony/oscache/base/Cache.getFromCache(Cache.java:199)
at com/opensymphony/oscache/general/GeneralCacheAdministrator.getFromCache(GeneralCacheAdministrator.java:132)
jedis2.1.0在高并发时偶尔会出现线程短暂的阻塞，resin服务没有挂起，还能正常访问