DB2 Version 9.7 for Linux, UNIX, and Windows

Memory usage restrictions for DB2 Express Edition and Workgroup Server Edition

What is the difference between the memory limits for DB2® Express® Edition and DB2 Workgroup Server Edition?

If you purchase DB2 Workgroup Server Edition V9.7 under the Processor Value Unit (PVU) charge metric, you can deploy it on a system which can use a maximum of 64 GB of instance memory, even if the server has more than 64 GB of memory. Starting in Version 9.7 Fix Pack 3a, the instance memory limit has been increased to 64 GB.

For DB2 Version 9.5 or higher, you can deploy DB2 Express Edition on a system with up to 200 VU, and it can use a maximum of 8 GB of instance memory, even if the system has more than 8 GB of memory. You can have multiple instances of DB2 Express Edition, but the combined memory of those instances cannot exceed 8 GB. For example, if you had 2 instances, each instance could only use a maximum of 4 GB of memory.

How can I change or limit the amount of memory used by a DB2 data server?

You can use the instance_memory database manager configuration parameter to specify the maximum amount of memory that the database manager is allowed to allocate from its private and shared memory heaps.

What are the restrictions for DB2 Express-C?
The following restrictions apply for DB2 Express-C V9.7 (no charge, non-warranted):
  • Up to two processor cores
  • No more than 4 GB of memory divided between your instances
How does IBM define a core?
Refer to the value unit terminology available on the Passport Advantage® Web site.
Multiple cores can fit onto a processor. For example, a dual-core chip contains one processor with two cores.