CSM, IDSM, ADSM Performance Problems or Memory Errors ? Increase Java Memory.
22 July, 2008 by Greg Ferro Print Posting
I have been getting out of memory errors in Java when running CSM and ASDM clients on MS Windows platforms. Here are some tips for improving Java performance, and letting you run more than one Java program / applet at the same time.
This is because Java allocates only a limited amount of memory at startup. Although the memory is allocated in certain classes, increasing the ‘heap size’ seems to have the most impact.
I have found that I get less memory errors, but I think that I also get much better applet performance. And CSM can be quite slow at times.
Products that Cisco engineers will find this useful for :
- Cisco Security Manager
- IDM on IDSM modules
- ASDM on PIX and ASA firewalls
- Access Control Server (Java in the web pages)
Leave a comment below if there are any more. Also if you know what the defaults are for Java 6.0, I can’t seem to find it mentioned anywhere.
Configuring the Java Memory heap size
Go Control Panel - Java - Select the VIEW button


Double click the “Java Runtime Parameter: (see the image below):
In the Java Runtime parameter field enter the following:
-Xms256m -Xmx1024m

Memory defaults
-Xmssize in bytes is the Minimum heap size. This will reserve this amount of memory when Java starts. Probably should keep it small for web applications that your browser might generate.
-Xmxsize in bytes is the Maximum Heap size. On 32-bit Windows systems with 4 Gb of RAM, there is a maximum heap-size limit of approximately 1.6 Gb. You may need to add the /3GB switch to the boot.ini file to get the full memory space so caution needed here.
I would suggest that you set it to no more than 1Gb (1024) , less if you don’t have a lot of memory.
Special Tip
Every time you update Java, you will need to go back and do this again. You can see from the screenshots that that there are three versions installed and each one has different parameters.
Isn’t Java wonderful ?











Great Post. This is ALWAYS an issue with people that run through our CSM training. Java is so touchy isn’t it!
Cheers!
Brandon