dual processor and single processor behaviour

[mkgarnek]

We have a memory leak problem with an application we have developed. When the application is deployed on a dual processor system, the heap usage grows until we get an OutOfMemoryError. When the application is deployed on a single processor system, the heap initially grows and then flattens out. Both systems are essentially the same and the data is the same. The only significant difference seems to be the number of processors.

We initially spent a number of weeks searching for memory leaks in our application and the various components in the system. We believe we eliminated those but we were still experiencing our memory leak. In the course of trying different things we eventually decided to test the dual processor as the cause.

We are planning to deploy the application on a different dual processor system to eliminate the actual server itself. In the meantime, we would like to know if anyone else in the JBoss community has experienced different behaviour between single processor and dual processor systems.

[darranl]

Which operating system and JDK are you using, this will probably have a major impact on how memory is allocated on a dual processor system.

[mkgarnek]

We have used a few combinations.

Windows 2000 Server + SP2, Java 1.4.2_01-b06
Windows 2000 Server + SP3, Java 1.4.2_01-b06
Windows 2000 Advanced Server + SP4, 1.4.2_04-b05

[shortpasta]

if this makes you feel better, i've seen 0 leaks on both a 2 cpu and 4 cpu windows system.

i started both installations with 3.2.4.RC1 and then upgraded to 3.2.4.RC1.

[mkgarnek]

Which JVM are you running 3.2.4 under?