Direct links to fixes
APAR status
Closed as program error.
Error description
WebSphere Application Server DynaCache provides the capability to limit the size in megabytes of each cache instance. This feature is available by implementing the com.ibm.websphere.cache.Sizeable Java interface. Cache entries used by the WebSphere Commerce price rule cache with JNDI name dmap/PR_Cache do not implement this interface. The result is that this capability cannot be used, and the Cache Monitor application shows the size of each cache entry as -1 (disabled). The WebSphere Commerce data cache provides a configuration setting to enable the Sizeable interface for other object caches, but it does not work for the dmap/PR_Cache object cache. The WebSphere Commerce data cache also provides a configuration setting to reduce the memory footprint of cached objects, but it does not work for the dmap/PR_Cache object cache.
Local fix
Problem summary
USERS AFFECTED: Any user wishing to limit the size of the price rule cache by specifying a size in megabytes. PROBLEM ABSTRACT: Reduce memory footprint of Price Rule object cache and implement the Sizeable interface. BUSINESS IMPACT: It is more difficult to manage the memory footprint of the price rule cache because the reduceMemory and sizeable data cache settings do not work for the dmap/PR_Cache object cache. Currently, without this feature, customers can limit the size of each cache instance by the maximum number of cache entries that can be contained in memory, and by the maximum size of the disk cache in gigabytes, but they cannot limit the memory footprint
Problem conclusion
This iFix implements the com.ibm.websphere.cache.Sizeable interface for cache entries used by WebSphere Commerce in the price rule cache with JNDI name dmap/PR_Cache when the iFix for WebSphere Commerce Feature Pack 4 APAR JR49826 is installed. It also implements the reduceMemory data cache setting. For backward compatibility, these capabilities are not enabled "out of the box" and must be explicitly configured in the CrossTransactionCache tag of the InstanceProperties tag in the wc-server.xml instance configuration file. The "sizeable" property is defined for the CrossTransactionCache tag: specify sizeable="true" to enable this capability. The "reduceMemory" property is also defined for the CrossTransactionCache tag: specify reduceMemory="true" to reduce the memory footprint of WebSphere Commerce object caches. A cache entry that implements the Sizeable interface provides an estimate of its memory footprint to DynaCache, allowing DynaCache to control the overall memory footprint of each cache instance. Test results have shown that the accuracy of the estimate can vary. Note: DynaCache will disable this capability for a cache instance if it detects that a cache entry that does not implement the Sizeable interface (for example custom cacheable commands in the baseCache) is placed into a cache instance. When this happens, a message like the following is placed in the SystemOut.log: DYNA1067E: The cache size in MB feature is disabled because the cached object is not sizeable. Note: While DynaCache automatically implements the Sizeable interface for servlet (JSP) cache entries, test results have shown that the sizes calculated for these entries can be significantly underestimated. For example, in some tests the actual memory footprint of the baseCache servlet cache was observed to be significantly larger than the calculated memory footprint reported by the cachemonitor application. For these reasons, it is generally not advised to specify the memory size in MB for servlet cache instances. Note: The normal cache maximum size setting is also used to limit the number of cache entries kept in memory. You should continue to specify a reasonable maximum size setting for each cache instance, to control the memory footprint and prevent potential out of memory conditions. ------------------------------------------------------------- The latest available maintenance information can be obtained from the Recommended Fixes for WebSphere Commerce technote: http://www.ibm.com/support/docview.wss?rs=3046&uid=swg21261296
Temporary fix
Comments
APAR Information
APAR number
JR49762
Reported component name
WC BUS EDITION
Reported component ID
5724I3800
Reported release
700
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2014-03-26
Closed date
2014-09-02
Last modified date
2014-09-02
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
WC BUS EDITION
Fixed component ID
5724I3800
Applicable component levels
R700 PSY
UP
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSYSYL","label":"WebSphere Commerce Enterprise"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0","Line of Business":{"code":"LOB31","label":"WCE Watson Marketing and Commerce"}}]
Document Information
Modified date:
11 December 2021