What is the recommended value for MAXDSIZ kernel tunable for java applications?

[PrasannaKumari]

The value of MAXDSIZ kernel tunable on two HP-UX hosts is 117440512 bytes ( 112 MB). Our java application is starting on one host while the application is crashing on the other HP-UX host giving the following error message.

Exception in thread "CompilerThread1" java.lang.OutOfMemoryError: requested 32756 bytes for ChunkPool::allocate. Out of swap space?
Possible causes:
- not enough swap space left, or
- kernel parameter MAXDSIZ is very small.

The host on which the application is running has more swap space being utilized compared to the host on which the application is crashing.

Can you please let me know what the problem could be and how to debug this issue further?

Is increasing the MAXDSIZ value the only solution for this as I learnt from the man pages that the default value of this 1 GB?

[sreekanthtm]

Hi,

How much is your Physical memory?
Please post the swapinfo -atm o/p also.

Check this link also
http://forums11.itrc.hp.com/service/forums/questionanswer.do?admit=109447626+1245136997222+28353475&threadId=198200

Rgds,
Sreekanth

[PrasannaKumari]

Physical memory details of the host
====================================
Memory Information:
physical page size = 4096 bytes, logical page size = 4096 bytes
Physical: 37729280 Kbytes, lockable: 25350920 Kbytes, available: 29174408 Kbytes

Swap space details
==================

)# swapinfo -am
Mb Mb Mb PCT START/ Mb
TYPE AVAIL USED FREE USED LIMIT RESERVE PRI NAME
dev 6144 0 6144 0% 0 - 1 /dev/vx/dsk/rootdg/swapvol
dev 2048 0 2048 0% 0 - 1 /dev/vx/dsk/rootdg/dumpvol
dev 1024 0 1024 0% 0 - 1 /dev/vx/dsk/dg01/swapvol2
reserve - 4839 -4839
memory 24806 6673 18133 27%

[Dennis Handly]

>The value of maxdsiz kernel tunable on two HP-UX hosts is 112 MB.

This is way too small for Java. Not sure why it works on one?

>Is increasing the MAXDSIZ value the only solution for this as I learned from the man pages that the default value of this 1 GB?

Yes. You should increase it to 1 Gb.

[sreekanthtm]

Hi,

Memory and swap configuration seems OK.
Increase the value of MAXDSIZ

# kmtune MAXDSIZ=2148483648

For setting the value 2GB

Rgds,
Sreekanth