Multiple threads stuck in native calls
I have a problem with an application running on Fedora Core 6 with JDK 1.5.0_08.
After some amount of uptime (usually some days) threads begin getting stuck in native methods.
The threads are locked in something like this:
"pool-2-thread-2571" prio=1 tid=0x08dd0b28 nid=0x319e waiting for monitor entry [0xb91fe000..0xb91ff7d4]
at java.lang.Class.getDeclaredConstructors0(Native Method)
or
"pool-2-thread-2547" prio=1 tid=0x75641620 nid=0x1745 waiting for monitor entry [0xbc7fe000..0xbc7ff554]
at sun.misc.Unsafe.defineClass(Native Method)
Especially puzzling to me is this one:
"HealthMonitor-10" daemon prio=1 tid=0x0868d1c0 nid=0x2b72 waiting for monitor entry [0xbe5ff000..0xbe5ff4d4]
at java.lang.Thread.dumpThreads(Native Method)
at java.lang.Thread.getStackTrace(Thread.java:1383)
The threads remain stuck until the VM is restarted.
Can anyone give me an idea as to what is happening here, what is causing the native methods to block?
The monitor entry address range at the top of each stuck thread is different. How can I figure out what is holding this monitor?
Any suggestions or advice will be greatly appreciated!
Thanks,
David