800xA PNSM Non Paged Pool Memory Monitor
PNSM (PC, Software & Network Monitoring) includes several IT assets in the IT OPC Server Network. The object "Basic Computer Asset" allows the system to monitor the use of several computer resources including non paged pool memory, a memory pool that is reserved for kernel and driver use. It is a useful monitor since it detects memory leaks, which consume system resources. The library object type for the Basic Computer Device by default sets the critical threshold to 150 MB. This value was more reasonable in Windows XP and Server 2003 systems, however, with Windows 7 and Server 2008 this kind of resource use is quite common and is not indicative of a performance problem. As a result, newer systems that employ the use of this asset monitor often receive unnessecary nuisance alarms.Symptoms:
There are ways to reduce NPPM on a computer: reducing driver use, disabling TCP Chimney offload on NIC cards and disabling unused NIC ports. This can reduce the number of instances that the NPPM will breach the 150 MB threshold, but it is more practical simply to raise the NPPM alarm threshold to a reasonable amount. A similar issue occurred for Harmony Connect and Process Portal B systems, where the threshold in the ABBresourceconfig.xml was too low for NPPM. A TC was included in Harmony Connect RU3 that changed the threshold to 800MB. It is reasonable to use this as a threshold for systems with Windows 7 and Server 2008, since it will reduce nuisance alarms, prevent Harmony Connect node resource alarms if they are being employed, and it will still effectively detect memory leaks in the system. To modify the threshold navigate to the object type "Basic Computer Device" and select the aspect "Basic Computer Device". In config, modify the default NPP threshold, save and apply the setting. Be aware that any time you modify an object type it will adjust all instances of the object that are governed by the template.