Below is what I see in my SMP server log, when I get that error:
<event date="12/16/2013 11:09:22.9852711 -05:00" severity="4" hostName="CLE5ALT30" source="Symantec.ITMSAdmin.Web.ComputerGroup.GetComputerGroupDetail" module="w3wp.exe" process="w3wp" pid="1032" thread="37" tickCount="464635109"><![CDATA[Child device guids found in 0.00 seconds.]]></event>
<event date="12/16/2013 11:09:22.9862712 -05:00" severity="4" hostName="CLE5ALT30" source="Symantec.ITMSAdmin.Web.ComputerGroup.GetGroupDetail" module="w3wp.exe" process="w3wp" pid="1032" thread="37" tickCount="464635109"><![CDATA[Computer Set Built in 00:00:00]]></event>
<event date="12/16/2013 11:09:22.9902716 -05:00" severity="4" hostName="CLE5ALT30" source="Symantec.ITMSAdmin.Web.v1.ITMSAdmin.GetComputerGroupDetail" module="w3wp.exe" process="w3wp" pid="1032" thread="37" tickCount="464635109"><![CDATA[Retrieved Computer Group Details in 0.00]]></event>
<event date="12/16/2013 11:09:24.4504176 -05:00" severity="4" hostName="CLE5ALT30" source="Symantec.ITMSAdmin.Web.Common.Timer..ctor" module="w3wp.exe" process="w3wp" pid="1032" thread="94" tickCount="464636575"><![CDATA[Started spTS_GetComputer]]></event>
<event date="12/16/2013 11:09:24.4534179 -05:00" severity="4" hostName="CLE5ALT30" source="Symantec.ITMSAdmin.Web.Common.Timer.Dispose" module="w3wp.exe" process="w3wp" pid="1032" thread="94" tickCount="464636575"><![CDATA[Retrieved spTS_GetComputer in 00:00:00.0020002]]></event>