Cacti presenting inconsistent graphs for few Windows servers

[Caliver]

Dear all,

We have Cacti configured for around 30 windows and Linux VMs and the graphs are representing correct information except 4-5 windows 2008 servers.This is happening in random manner and gets fixed each time after reloading the "data query"

The problem is of 2 types
1.for some servers the physical memory size shows incorrect and gets changed automatically within a months time
2. The graphs are not consistent . it breaks in between for few hrs and returns to normal again

Attached file shows the trouble pattern

Would appreciate if I can get any suggestions to fix this

Regds,
Caliver Team

[BSOD2600]

It's a known problem that the Windows disk OIDs (which include memory) are quite laggy with response. Typically increasing the snmp timeout to 3-5 seconds solves the issue.