High Mem Util on HP-UX 11.0

[Benjamin McCartney]

Dear experts,

I am trying to perform some tuning of our environments, consisting of two N-class servers with 4GB memory. I have approx 12 Java apps running on these consuming 30-40MB memory each with a couple hitting about 120MB.

Using glance, I noticed that the overall memory utilisation of the machines is about 96-99% constantly. Some quick maths indicated that something other than my apps is eating considerable amounts of memorys (i.e. GBs).

Just wondering if anyone has any ideas on how to resolve this, or whether this is a feature of the HP-UX 11 platform in terms of how it manages memory.

Thanks,
Ben

[Patrick Wallek · Accepted solution]

First thing I'd check is your dbc_max_pct kernel parm. If it is still at the default of 50, then you need to modify it. With 4GB of RAM you could probably safely set it down to 8 or 10.

This would lower your max buffer cache size from 2GB to 320-400MB, which is much more reasonable.

[Ravi_8]

Hi, Ben

You also need to check for memory leak in the applications running.

[Richard Johnson_1]

Ben,

Also, if you have Glance installed then you can sort the process list by memory utlization to determine which processes are using the most memory.

Regards,

Rich

[Uncle Liew]

Besides than the Kernel Parameter, do make sure the latest recommended Java Patches is installed based on:

http://www.hp.com/products1/unix/java/infolibrary/patches.html

If your Java version is Java 1.3.x, please do upgrade to the latest Java 1.3.1.06:
http://www.hp.com/products1/unix/java/java2/sdkrte1_3/downloads/index.html

If your Java version is Java 1.4.x, please do upgrade to the latest Java 1.4.0.01:
http://www.hp.com/products1/unix/java/java2/sdkrte14/downloads/index.html

Note Java 1.3 & 1.4 can run currently in your system. Diff dir: /opt/java1.3 & /opt/java1.4 ... you need play around with the env PATH if you need to switch with each other.

The above solution has help some of my Corporate Customer when doing migration from Java 1.2 --> Java 1.3 or Java 1.3 --> Java 1.4