Ihave been checking out this CLR_AUTO_EVENT, according to performancedashboard and sys.dm_os_wait_stats we have lot of wait there. Morethen 45% of total wait on the server. I fired up my local server andinstalled assembly a sample table and started to reproduce thebehavior. After running more 1000 call to function CLR_AUTO_EVENT start to accumulate. I started to comment out a bit of the logic. But still CLR_AUTO_EVENT builds up. <Microsoft.SqlServer.Server.SqlFunction()> _ Public Shared Function fu_VarFilter( _ ByVal varKodIn As SqlString, _ ByVal varFilterIn As SqlString _ ) As SqlBoolean â€˜Normal there is logic here that select what row to return. But commed it out and still the ' CLR_AUTO_EVENT builds up. Return True End Function Call select * from tfanvar WHERE dbo.fu_VarFilter('21-1-1-1-3', VldVar) = 1 Inthis way the whole table is scan and all rows are delivered , With thiscompletely empty function I get CLR_AUTO_EVENT start to accumulate Shall I even care about this wait? Or what? Is that normal?