Read memory usage from vmware ESX 2.5.x, result in %

Hi..

i'm trying to make a resource monitor reading the memory usage from vmware ESX server 2.5.x, i can read the installed memoty in the server and available memory, and thought that from this i maby could do something like this..

to get a percentage value, to show tha same gauge as all other servers..

</DEFAULTGRAPH>
<DEFAULTGRAPH Name="Esx-MemoryUtilization">
<YAXISTEXT>Percentage</YAXISTEXT>
<DISPLAYNAME>ESX Memory Utilization</DISPLAYNAME>
<name>EsxMemoryUtilization</name>
<Vendor>SNMP</Vendor>
<Monitor>Resource</Monitor>
<Description>Monitors Memory usage in Vmware ESX server</Description>
<oid>(100-((.1.3.6.1.4.1.6876.3.2.3.0/.1.3.6.1.4.1.6876.3.2.1.0)*100))</oid>
<type>node</type>
<interval>900</interval>
<THRESHOLDENABLED>false</THRESHOLDENABLED>
<DIAGNOSTICNAME>ESX-Sol-Memory</DIAGNOSTICNAME>

//Patrik Nilsson