DB2 Express Edition and DB2 Workgroup Server Edition memory limits If you are installing DB2 Express Edition, the maximum allowed memory for the instance is 4 GB. If you are installing DB2 Workgroup Server Edition, the maximum allowed memory for the instance is 64 GB. The amount of memory allocated to the instance is determined by the INSTANCE_MEMORY database manager configuration parameter. Important notes when upgrading from Versions 9.5 or 9.7: v If the memory configuration for your Versions 9.5 or 9.7 DB2 database product exceeds the allowed limit, the DB2 database product might not start after upgrading to the current version. v The self tuning memory manager will not increase your overall instance memory limit beyond the license limits.