Help! Hotspot Crashes

[Peter Chang]

I have a production system running a Java application server with 1GB min/max heap memory.

The JDK version is 1.3.0.00.

However, every now and then I am getting:
OutOfMemoryException
<< not stack trace available >>

{Lots of thread dumps}
#
# Java version:
# HotSpot VM (mixed mode)
#
# HotSpot Virtual Machine Error, Unexpected Signal 11
#
# occurred at pc=c0166624
# Error ID: /CLO/Components/JAVA_HOTSPOT/Src/build/hp-ux/../../src/os/hp-ux/vm/os_hp-ux.cpp, 3050
#

The verbose GC shows the heap utilisation is always below 25% (ie, max is 250MB heap memory in use).

I tried to tune the hotspot parameters but:
java -hotspot -XX:NewSize=128m -XX:MaxNewSize=128m -version

dumps core straight away!

I have to use:
java -hotspot -XX:NewSize=128m -XX:MaxNewSize=256m .......

to work around this.

But it still dumps core after some time.

This is driving us crazy. It would be much appreciated if you can shed some light on this urgent problem.
Many thanks.

[Bill McNAMARA_1]

have you followed the kernel tuning recomendations on hp.com/go/java ?

Later,
Bill

[Bill Hassell]

Out of memory really means:

- Out of swap space, or
- Exceeded kernel limit maxdsiz

swapinfo -tm will tell you about the current state of swap space. If the total line is getting up to 75%, you may need to add more swap (but better performance will result if you add more RAM first).

For maxdsiz, bump up the value from it's (fairly low) limit of 64 megs to about 500 megs. This is simply a runaway-program fence to keep bad programs from using all the virtual memory.

[Sanjay_6]

Hi Peter,

Have a look at the thread below,

http://us-support.external.hp.com/cki/bin/doc.pl/sid=79798fd30113f56186/screen=ckiDisplayDocument?docId=200000048086757

http://us-support.external.hp.com/cki/bin/doc.pl/sid=79798fd30113f56186/screen=ckiDisplayDocument?docId=200000052783182

Seems like you need to look into your kernel parameters.

Hope this helps.

Thanks

[Brian Williams_5]

I am seeing a very similar error:

# Java version:
# HotSpot VM (mixed mode)
#
# HotSpot Virtual Machine Error, Unexpected Signal 11
#
# occurred at pc=c013e844
# Error ID: /CLO/Components/JAVA_HOTSPOT/Src/build/hp-ux/../../src/os/hp-ux/vm/os_hp-ux.cpp, 2998
#

while using:

java version "JavaVM-1.3.0.01"
Java(TM) 2 Runtime Environment, Standard Edition (build jinteg:02/14/01-23:51)
HotSpot VM (build 1.0.1fcs jinteg:02/15/01-02:43 PA2.0, mixed mode)

on my HP-UX 11.00 dual PA-RISC CPU machine.

I have my kernel parameters set correctly, too, I think. See the attachment to this posting, which is the output of the "kmtune" command.

I have seen the HP-UX Java VM crash before when I had forgotten to compile some of my JNI code with the +z or +Z switch (PIC), but I am perplexed about this problem.

Also, the core file that is being written is so big that my disk is full before the core file is complete. Gahh!