Receiving JVMCL052: Cannot allocate memory

Issues and Questions related to running Apache Tomcat on z/OS
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dstafford
Posts: 7
Joined: Mon Aug 28, 2006 4:07 pm

Receiving JVMCL052: Cannot allocate memory

Post by dstafford »

I am receiving the message "JVMCL052: Cannot allocate memory....." after tomcat comes up. The application is an AXIS based WAS application, has a rather large cache file that gets read into resident heap. The first connection to this service causes the message to be received.
the options are: IBM_JAVA_OPTIONS=-Xms512m -Xmx1400m ......
I am requesting a region size of 0M as follows:
Region requested = 0K, Actual below/above limit = 8M / 1767M

Has anyone encountered this before? (By the way, this same application works just fine on a Linux server).

Thanks
dovetail
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Posts: 2022
Joined: Thu Jul 29, 2004 12:12 pm

Post by dovetail »

The error message JVMCL052 indicates that an allocation to the C / LE heap failed. The usage of virtual storage by the SDK is covered in CH 19 of the SDK 1.42 Diagnostics guide.

The likely problem is that you are asking for a maximum Java heap of 1400mb of 1700mb total available in the address space. What left is used by all of the internal JVM functions, including JIT representations of your classes.

The reason that it runs out is that the 1400mb max heap is malloc'd from the LE heap as soon as the JVM is started. So you are probably running of what is left for non-java-heap purposes.

So, try running with a smaller max heap size.
For more details, check out Ch 19 in the SDK 1.4.2 Diagnostics Guide.
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