Confused about a node's memory utilization

I am confused about something. Upon viewing details for a specific node, I have added Min/Max/Avg Memory utilization, as well as Percent Memory Used charts. Both are showing me the same thing - that all memory in my node (8G) is in use. Yet if I look at TaskMgr (it's a Win2003 R2 Enterrpise server), it shows me peak memory use is well below that - 2.75G. Available memory shows as 6G. And those figures seem correct, for what this server does (it's a Lotus Notes mail server).

So what am I misunderstanding? I want to monitor memory utilization, and the values from TaskMgr seem much more realistic to me, rather than 100% memory utilized ... why is it showing 100% memory used? What do I need to do, to see the 2.75G utilization that TaskMgr shows me? and historical usage like that.

Or should I be adding some other node historical charts, to see what I'm looking for?

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chris.newton

I think this is a bug because it only happens on servers that have lotus notes (domino) installed. I am having the same issue and it would be nice to resolve because it confuses the hell out of people.

PHA

OK ... but I see the same thing (Avg Mem Used equal to Total Physical Memory, not Physical Mem in use) on non-Domino servers. I have servers running BEA WebLogic and it's Tuxedo product that are also showing as 2G Avg Memory Used (which is the total physical memory), and not the 1.4G that TaskMgr and the Physical Memory entry under Disk Volumes shows me.

You're right that I don't see this oddness with my MS AD controllers, or the fewe MS SQL cluster nodes I have spot checked. But it's not just Domino servers.

(and how can that be, anyway? Why would the Domino servers be reading memory info from a different set of counters, only under Orion? Doesn't Orion read the Windows counters, which are showing me the correct info?)

justty

I am on 9.5 SP4, I found this in the admin guide.

Monitoring Windows Server Memory

When Orion NPM polls a Windows server for CPU load and memory utilization, it pulls the amount of physical memory (this is the 100% number) and then it totals the amount of memory in use by each allocation to compute what percentage of the physical memory is in use. This can result in memory utilization readings over 100%, as many applications pre-allocate memory and swap before it is actually needed. To work around this, you can also add physical memory as a volume for these servers within Orion NPM. When monitored as a volume, the values will be more in line with your expectations.

However, when I started reviewing other comparable products, they reported memory utilization on Domino correctly, but a handful did mention the pre-allocate issue.