CPU scheduling and thread priority
GlobalTimerResolutionRequests
The Windows 10 2004 timer change, and what it means for latency tools
Last updated
What changed about timer resolution in Windows 10 2004?
Before Windows 10 version 2004, when any process requested a higher system timer resolution the change applied globally. From 2004 onward the raised resolution applies only to processes that requested it, so a background tool can no longer raise it on a game's behalf. GlobalTimerResolutionRequests restores the old global behaviour.
Registry location and values
GlobalTimerResolutionRequests
- Location
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\kernel- Value name
GlobalTimerResolutionRequests- Type
REG_DWORD- Default
- not present (per-process behaviour on Windows 10 2004+)
| Value | What it does |
|---|---|
1 | Timer resolution requests apply globally, as before Windows 10 2004. |
0 | Per-process behaviour. |
What Windows actually does with this
Timer resolution controls the granularity of timer interrupts and therefore how precisely a thread can be woken. A process calls timeBeginPeriod to request finer resolution. The 2004 change scoped that request to the requesting process, because a global raise cost power on machines where only one application needed it.
What it affects
Whether a third-party latency or timer tool can raise resolution for other processes. If a game requests fine resolution itself, it gets it either way, and this setting changes nothing for that game.
Is it worth changing?
Only relevant if you are using an external tool that sets timer resolution and expecting it to affect a different process. If your game requests the resolution it needs -- and most do -- this changes nothing. Restoring global behaviour raises timer interrupt frequency machine-wide, which costs power and, on laptops, battery. Microsoft's own guidance is that applications should not raise timer resolution unless necessary, precisely because of that cost.
What can go wrong
Higher idle power consumption and more timer interrupts machine-wide. On laptops this is measurable.
How to undo it
Delete the value and restart.
Create a System Restore Point before editing the registry. Every setting on this page is reversible, but a restore point is the difference between undoing one change and reinstalling Windows.
Which Windows versions this applies to
Windows 10 version 2004 and later, Windows 11.
GlobalTimerResolutionRequests: common questions
Is 0.5ms timer resolution better than 1ms?
It is finer, which means a thread can be scheduled to wake closer to its intended time. Whether you can perceive that depends entirely on whether anything in your chain was waiting on a timer with that granularity. It is not free: more timer interrupts means more power and more wakeups.
Sources
Does JINSHI Tweaks change this?
This page documents settings that correspond to the following toggles in JINSHI PC Tweaks: Apply Timer Resolution Requests Globally, Disable TSC Synchronization.
The reference above is written to be usable without the product. Everything here can be applied by hand for free. What the application adds is that the change is applied in one pass, a System Restore Point is created first, and each toggle can be reversed individually.