THIS WILL DRAMATICALLY REDUCE YOUR LATENCY!

Summary

In this follow-up video on the Windows scheduler guide, the presenter introduces a tweak to reduce system interrupts and latency significantly. By adjusting the 'processor performance time check interval' setting to 5,000 milliseconds, the video demonstrates a 10-fold decrease in system interrupts and improved latency across games and applications. The tweak targets the 'PPM perf action' symbol, which is related to power management. The presenter also recommends using tools like 'xerf' for analyzing system latency and suggests further tweaks, such as disabling right cash buffer flushing on SSDs, to achieve even better performance.

Takeaways

• 😲 The video is a follow-up on the ultimate Windows scheduler guide, focusing on a specific system tweak to reduce interrupts and latency.
• 🔧 A reserved CPU set tweak allows changing Windows scheduling, moving all OS operations off core zero, which was previously thought impossible.
• 🔬 The script mentions using 'media experience analyzer' to identify a non-compliant driver and kernel symbol related to power management.
• 🛠️ 'Power Settings Explorer' software is recommended for adjusting the 'processor performance time check interval' setting, which is key to the tweak.
• ⏱️ The default setting for 'processor performance time check interval' is 15 milliseconds on high performance plans, which is considered high.
• 🔍 This setting determines how often the OS re-evaluates power-saving states, and reducing it can significantly cut down on unnecessary updates.
• 📉 Setting the interval to 5,000 milliseconds can reduce system interrupts dramatically, improving latency across the board.
• 🛑 Tools like 'xerf' and 'latencymon' are recommended for analyzing system latency and the impact of the tweak.
• 🚀 Disabling 'right cash buffer flushing' in device manager for SSDs is another tweak mentioned to reduce system activity.
• 🔧 Additional tweaks in power plans and device manager can further minimize system interrupts, leading to a quieter and more efficient system.
• 👍 The video emphasizes that these tweaks can greatly improve system performance without the need for expensive hardware upgrades.

Q & A

What is the main focus of the video script?

The main focus of the video script is to provide a follow-up guide on reducing system interrupts and latency in Windows, specifically by tweaking the 'processor performance time check interval' setting.

What is the significance of reducing interrupts and latency in a system?

Reducing interrupts and latency is significant because it can improve system performance, particularly in scenarios requiring high responsiveness, such as gaming or running latency-sensitive applications.

What tool is mentioned for changing the way Windows scheduling works?

The tool mentioned for changing the way Windows scheduling works is 'Power Settings Explorer', which is not typically available by default.

What does the term 'PPM perf action' stand for?

The term 'PPM perf action' stands for 'Processor Performance Management perf action', which is related to actions performed for power management.

What is the default setting for 'processor performance time check interval' on high performance plans?

The default setting for 'processor performance time check interval' on high performance plans is 15 milliseconds.

What is the purpose of the 'processor performance time check interval' setting?

The purpose of the 'processor performance time check interval' setting is to specify the amount of time that must expire before processor performance states and parked cores may be re-evaluated.

What is the impact of setting the 'processor performance time check interval' to its highest value of 5,000 milliseconds?

Setting the 'processor performance time check interval' to 5,000 milliseconds can dramatically reduce the number of system interrupts, potentially by 10 times, and significantly lower latency.

What tool is recommended for analyzing system latency?

The tool recommended for analyzing system latency is 'xerf', which is described as a better and almost infinitely better version of 'latencymon'.

What additional tweaks can be done to further reduce system interrupts and latency?

Additional tweaks include disabling right cash buffer flushing in the device manager for SSDs, and adjusting various settings within the power plans and device manager.

What is the final impact of applying the suggested tweaks on system activity?

The final impact of applying the suggested tweaks is a dramatic reduction in system activity, with only the Nvidia driver showing a significant number of interrupts due to its nature of updating screen frames and refresh rates.

How can viewers test and analyze the tweaks mentioned in the video?

Viewers can test and analyze the tweaks by adjusting the 'processor performance time check interval' to 5,000 milliseconds, and then using tools like 'xerf' and 'latencymon' to measure the impact on system latency and interrupts.

Outlines

00:00

🛠️ Optimizing Windows for Reduced Latency

This paragraph introduces a follow-up video on the Windows scheduler guide, focusing on a tweak that significantly reduces system interrupts and latency. The author highlights the importance of this tweak in conjunction with reserved CPU sets, which allows for a complete change in Windows scheduling. The main culprit identified is the 'PPM perf action', which is related to power management and performance. The video suggests using Power Settings Explorer to adjust the 'processor performance time check interval' from its default of 15 milliseconds to a higher value of 5,000 milliseconds, which can drastically reduce system interrupts and improve latency. The author recommends using 'xerf' for analyzing system latency and provides evidence of the effectiveness of this tweak.

05:00

🔍 Further Tweaks for System Performance

The second paragraph delves into additional tweaks that can be made to further optimize system performance. It discusses changing settings in the power plans and device manager, such as disabling right cash buffer flushing on SSDs. The author explains that by tweaking the 'processor performance time check interval' to 5,000 milliseconds, the system's interrupt activity can be reduced to a fraction of its normal state. The paragraph also mentions the Nvidia driver as an exception, due to its nature of updating screen frames and refresh rates, which naturally results in more interrupts. The author provides a visual comparison using tools like 'latencymon' and 'omit' to demonstrate the significant reduction in latency and system activity after applying these tweaks, emphasizing the effectiveness of these changes in improving system performance without the need for expensive hardware upgrades.

Keywords

💡Windows Scheduler

The Windows Scheduler is a component of the Windows operating system that manages the allocation of processor time to the various processes running on the system. It is crucial for ensuring that tasks are executed efficiently and in a timely manner. In the video, the presenter discusses how tweaking the Windows Scheduler can reduce system interrupts and latency, which is a key aspect of optimizing system performance for tasks like gaming or running heavy applications.

💡Interrupts

Interrupts in computing refer to the signals sent to the processor by hardware or software indicating an event that needs immediate attention. Reducing the number of interrupts can lead to improved system performance by minimizing the processor's time spent switching between tasks. The video emphasizes the importance of reducing interrupts as a means to decrease system latency and improve the overall responsiveness of Windows.

💡Latency

Latency in computing is the delay before a transfer of data begins following an instruction for data transfer. Lower latency is desirable in many applications, especially in gaming and real-time processing, where quick response times are critical. The video discusses how certain tweaks can dramatically reduce latency, which can lead to a smoother and more responsive user experience.

💡Reserved CPU Sets

Reserved CPU Sets is a feature that allows users to allocate specific processor cores for certain tasks, thereby improving performance and reducing latency. In the context of the video, the presenter mentions that adjusting the Reserved CPU Sets can help in managing how Windows schedules tasks, which can be particularly useful for high-performance computing needs.

💡Processor Performance Management (PPM)

Processor Performance Management (PPM) is a feature in modern processors that dynamically adjusts performance and power consumption based on the workload. The script mentions 'PPM perf action', which seems to be related to power management and performance adjustments. The video suggests that tweaking settings related to PPM can have a significant impact on reducing system interrupts and improving latency.

💡Power Settings Explorer

Power Settings Explorer is a software tool that allows users to view and modify power settings on their Windows system. In the video, the presenter uses this tool to adjust the 'processor performance time check interval', which is a setting that controls how often the system re-evaluates power states and parked cores. By changing this setting, the presenter demonstrates a significant reduction in system interrupts.

💡DPC (Deferred Procedure Call)

DPC stands for Deferred Procedure Call, which is a mechanism in Windows for executing code at a lower priority than the current executing code. High DPC latency can be a sign of system inefficiency. The video uses DPC as a metric to measure the effectiveness of the tweaks discussed for reducing system latency.

💡ISR (Interrupt Service Routine)

ISR refers to Interrupt Service Routine, which is a function called by the operating system in response to a hardware interrupt. The video mentions ISR in the context of analyzing tools that measure the number of interrupts generated by the system, which is an indicator of system performance and efficiency.

💡Xerf

Xerf is a software tool mentioned in the video as an improved version of LatencyMon, used for analyzing system latency. It provides detailed information about the latency generated by different drivers and services, which is crucial for identifying bottlenecks and areas for optimization in system performance.

💡Nvidia Driver

The Nvidia Driver refers to the software that enables the operating system to communicate with Nvidia graphics cards. In the video, the presenter notes that the Nvidia driver is one of the few services that continues to generate a significant number of interrupts even after applying the discussed tweaks. This suggests that the driver plays a key role in the system's performance, particularly in graphics-intensive applications.

Highlights

Introduction to a follow-up video on the ultimate Windows scheduler guide.

A specific system tweak can dramatically reduce interrupts and latency.

The importance of reducing latency for media experience and system performance.

The discovery of a driver and kernel symbol not obeying reserved CPU sets.

Explanation of reserved CPU sets and their impact on Windows scheduling.

Introduction of the PPM perf action symbol related to power management.

Use of Power Settings Explorer to modify system settings.

Details on the 'processor performance time check interval' setting.

Impact of setting the time check interval to 5,000 milliseconds on system interrupts.

Introduction of xerf as a superior tool for analyzing system latency.

Analysis of system interrupts with the time check interval set to 15 milliseconds.

Demonstration of the significant reduction in interrupts by setting the interval to 5,000 milliseconds.

Further tweaks to reduce system interrupts and improve latency.

Disabling right cash buffer flushing in device manager for additional latency reduction.

Verification of the effectiveness of the tweaks using multiple analyzing tools.

Reduction of system activity and latency with the 5,000 millisecond setting.

Acknowledgment of the role of the Nvidia driver in system interrupts.

Final demonstration of latency reduction using a different latency monitoring tool.

Recommendation to test and analyze the tweaks for personal system improvement.

Closing remarks and call to action for subscribing to the channel.

Transcripts

all righty guys well welcome to the

video so today what I wanted to do is a

follow-up video on the ultimate Windows

scheduler guide and the reason why I

wanted to make this video is that there

was one specific tweak that you can do

to your system to dramatically reduce

the amount of interrupts and latency

within your system and the reason why

this matters so much guys is because in

combination with the tweaks that I've

already mentioned before with the

reserved CPU sets what I noticed is that

when I ran media experience analyzer

there was only one specific driver and

one specific kernel symbol that was not

obeying the reserved CPU sets which if

you're not familiar with allows you to

basically change the way that Windows

scheduling works entirely so you can

basically move all of your operating

system off of core zero which again I

originally thought was basically all but

impossible because I had never seen

anybody um have any software that could

override it in a way that actually

worked at a fundamental level with even

the current drivers so you guys are want

to going to check that out because it's

going to be a really cool guide that

you're going to probably enjoy learning

about but onwards with this video the

one symbol is known as PPM perf action

and what this seems to stand for is

processor Performance Management perf

action so performing an action for power

management and so what I noticed is that

a lot of people online were saying that

this was related to for example

something like speed step speed shift

all sorts of different um Dynamic

changing of frequency um sort of tools

that help save power boost performance

all that fun stuff so what I did is as I

downloaded a software known as the power

settings Explorer and this is normally

not something that you can have

available already so I'll link it in the

GitHub description as well and you guys

can actually you know figure it out and

download it for yourself but if you go

into there there's one specific setting

processor performance time check

interval Well normally this is defaulted

on the high performance plan

and it's normally set to a value of 15

milliseconds which is a very high amount

considering how often this is going to

be actually updating so what this

specifically says is specify the amount

that must expire before processor

performance States and parked cores may

be re-evaluated in milliseconds so this

is essentially checking how often the

operating system needs to change certain

power saving States within the system

but as we all know most of the way the

reduces latency is by disabling power

saving features so this essentially is

updating for no reason and this seems to

also apply for all of the different

games and actual latency tests that I

ran it doesn't seem to do anything so

long as you don't actually need to have

um any sort of parked cores moved or

changed or power States actually you

know re-evaluated so if you set this to

the highest value of 5,000 you can

dramatically reduce the amount of

interrupts on the system by an absolute

Ely unbelievable amount so I ran a bunch

of different DPC and ISR analyzing tools

and software and so the one you guys are

wanting going to check out is what's

known as xerf and it's basically a much

better an almost infinitely better

version of latencymon because there's a

lot of different flaws with that

software but exper gives you all of the

same different things that you're going

to want to use to actually analyze you

know the latency within your system so

normally with this set to 15

milliseconds it will be generating

almost

113,000 interrupts on your system which

is an absolutely insane amount

considering just how much of it is

related to just the kernel alone of a

100,000 interrupts are coming from just

the kernel alone so that's why I wanted

to analyze the driver of the kernel

specifically to see if I could find a

way to reduce this even if by a smaller

amount well this was the main reason why

I wanted to make this video because this

is this is how unbelievable this tweak

is when you set it to the highest value

of 5,000 milliseconds you reduce the

amount of interrupts by on your system

by 10 times so we have cut the amount of

interrupts into oneth and not only that

but the latency is dramatically reduced

across the board regardless of whatever

driver or service that you're talking

about so if I go into the 15 millisecond

version right here you'll notice that we

have tons of latency in 64 32 and 16

microc interrupt latency times which is

very high considering you can normally

get it down to about 1 to 20

microseconds so this dramatically

reduces the amount of noise and activity

that the colel is actually using but

there also are even more tweaks that you

can do for example if you go into the

device manager and you go into one of

the ssds you can disable right cash

buffer flushing that's another example

of one and so for example down here on

the nvme and the storage port

if you enable this for example and do a

bunch of whole other tweaks as well like

turning on specific settings and turning

off specific settings and then you can

just mess with them inside of the power

plans and the device manager as well but

if you go even further you can reduce

the amount of interrupts in your system

to 100th of what it normally runs

at and that's just from a few small

tweaks from one tweak alone we already

reduced the amount of interrupts by 10

times and with just a little bit more

diligence and some small tweaks on the

operating system which don't impact

anything they don't change anything

about the system they just change small

little tiny monitoring metrics that

don't actually do anything we can reduce

the actual activity on across the board

for all of these different drivers and

services and are the only service that

has anything more than a couple of

interrupts is just the Nvidia driver

which go figure because you're going to

it's it's going to be updating the

frames per second of the screen and the

refresh rate and stuff like that so it

should be having a lot of interrupts

happening with it

so basically once we change

that from the normal state of 15

milliseconds to

5,000 the activity of Windows looks like

this now and like I said you can still

see the PPM Perfection is highlighted in

purple rather than

blue the actual activity of the

operating system is reduced dramatically

and across the board with a bunch of

other different analyzing software it is

still the same so for example in

latencymon here is it running at 15

milliseconds you can see there are tons

and tons of interrupts being

generated this is with it at

5,000 and this has been further actually

verified through omit which again credit

to him as well because he was

instrumental in reverifying this

information that I had discovered so it

was very helpful to make sure because I

wasn't I wanted to make sure that this

was actually the default value and that

this was actually applying for multiple

systems not just mine alone so this has

been reverified and you guys are going

to want to check out his actual GitHub

page and the information and

documentation about this he's been

instrumental and he's a really awesome

guy so we've seen all of this different

reductions in latency and interrupts and

activity and that is an unbelievable

amount of change for just a simple few

tweaks and finally the last one I'll

show just because I know some people

only like to see one specific type of

measurement of metric which is basically

another uh latencymon tool so this is

what it normally runs at with

point or for 15 millisecond

intervals this looks fairly good this is

actually not bad at all this is very low

but this is actually a very low amount

in consideration to what you can get

with just changing this one tweak alone

so with this one tweak with the the time

check interval it drops it all the way

down to 6 and I have single digit

microsecond

latency an absolutely amazing tweak and

so I recommend that you guys do this for

yourself test it analyze it because I

see no reason why you would need to have

this set to an insanely high value of 15

milliseconds because if you go into the

power settings Explorer the way you can

actually make it reveal itself is by

unselecting this and it will show you

right here high performance power plan

is set to 15

milliseconds and so yeah guys I hope you

enjoyed this video I hope that you guys

really enjoy this content and I hope

that it actually is helping you with

your system I've had a lot of fun and

the comments have been rather amazing

you guys are awesome please consider

subscribing to the channel if you do

appreciate this

content I do appreciate all of the

different kind of stuff that you guys

leave for questions and feedback and my

goal is basically just to help everybody

get a much better running system without

having to spend hundreds and thousands

of dollars on different Hardware or

different upgrades in your system so

yeah guys have a good one my name is

savis and I'm out