- Service: PSched - A standalone Windows 2003 Enterprise server had this Application Log event entered 10 times over the last 13 days, only once on any given day, generally occurring 24 hours plus 15-30 minutes after the last event. Performance was not being monitored. %SystemDirectory%\Drivers\PSched.sys seems to be the Packet Scheduler for QoS, and can be performance monitored. This computer does not have Qos installed. This machine has recently been locking up (touchpad memory violations) and has had corrupted Registry hives restored at reboot.
I found a bad Registry setting at HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\windows\Psched. NonBestEffortLimit was set to 0xfffffffb(4294967291). By default, it should be 0x00000014(20). Even at 100% bandwidth it would only be 0x00000014(100).
I checked two other places for incorrect values:
1. In gpedit.msc at Computer Configuration\Administrative Templates\Network\QoS Packet Scheduler no settings were defined.
2. In the Registry there were no NIC settings at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\PSched.
I set NonBestEffortLimit to the default 0x00000014(20) at HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\windows\Psched.
I fixed the lockups by setting DisableHeapLookaside to 1 for the video and touchpad drivers. See ME195009
PSched related links: “NonBestEffortLimit”, “Manage the Reserved QoS Bandwidth”, “QoS Bandwidth Reserve Setting”, and ME316666