Had this problem with SBS 2008 server last week.
The server disk usage was high with no particular reason, the service useing all the disk resources was mssql.exe reading from SBSMonitoring.mdf.
Searching the net took me to a TechNet post talking about this exact issue.
After applying this fix everything got back to normal.
I’m posting this here as a reminder to myself and to others with this kind of problem.
Open the SQL Management Studio and connect to the SBSMonitoring instance.
Create a New Query and paste this text into the query and execute the query:
SE SBSMONITORING GO CREATE NONCLUSTERED INDEX [IDX_Alerts_GetAlertsPerID] ON [dbo].[Alerts] ( [DefinitionID] ASC, [ComputerID] ASC, [DateOccured] ASC, [IsSet] ASC, [ID] ASC ) GO CREATE NONCLUSTERED INDEX [IDX_WMICollectedData_GetSecurityProductPerComputer] ON [dbo].[WMICollectedData] ( [WMIInstanceID] ASC, [WMIPropertyID] ASC, [DateCollected] ASC, [ID] ASC ) GO create index IDX_WMIObjectProperties_ObjectID on WMIObjectProperties(ObjectID,ID) Go create index IDX_WMIObjectInstances_ObjectID on WMIObjectInstances(ObjectID,ID)
I hope this helps.