FIX for Win7 i7 sluggish performance

Hi Everyone

I just found a great fix to stop win7 parking the cores when Idle.

This is an aggressive power saving approach which makes the system feel sluggish and underpowered..

I've just tried it and my system really feels snappier, although I haven't tried any benches. Try it for yourself and see!

from:
UltimateComputers.net Forum - View topic - Disable Core Parking Windows 7 Tweak may improve performance

Who is affected
It only applies to Windows 7 X64 and X32 and only in systems using more than 2 physicial CPU's and/or more than 2 "logical" cores - ie: Core i7's.

The Problem
See here for a bit of info / explanation / more info about CPU Core Parking - Windows 7 / Windows Server 2008 R2: Core Parking / Intelligent Timer Tick / Timer Coalescing - Ask the Performance Team - Home - TechNet Blogs

Core Parking is a feature of Windows 7 that is causing rare performance problems. I don't notice it on my home i7 / Win7 system but some people are getting microstutters and odd behavior in certain programs. Without the following " tweak" you may see CPU spiking in your programs and Windows Task Manager - some CPU cores will be "turned off" / "parked" depending on load and they will be dynamically turned on or off and dynamically loaded up or down as the system deems necessary - the scope for glitchs / pops / clicks / droputs etc.... in such an environment is simply enormous. To the best of my knowledge, there is no known "switch" to turn it off - no utility I am aware of to "tweak" it off.

The Fix
- Go to Regedit
- Select Edit > Find... and find this key: " 0cc5b647-c1df-4637-891a-dec35c318583 "
UPDATE: Try searching instead for "Specify the minimum number of unparked cores/packages allowed (in percentage)." (WITHOUT QUOTES)
- Within this key, there is a value called: " ValueMax " This value represents the % number of cores the system will park
- Change the value of " ValueMax" to 0 so that, it matches " ValueMin "
- You will have to find the key a few times and repeat the process for each time it is found - the number of instances will depend on the number of power profiles in your system. To do this go back up to Edit > Find Next. (I had 3 instances of this key in my registry.)
- Do a full shutdown and power-off and cold-re-start.

This seems to work better.[/COLOR]

 

Is this going to keep turbo boost from kicking in?

 

No, it's only stopping win7 from parking the idle cores (which makes them sluggish to respond).

It is making the benches run slightly higher. The mouse pointer actually moves at full frame rate too. Before it would sluggishly refresh every few frames, now it actually seems to be acting like a high performance machine.. Woohoo!

 

the fix stops the touchpad from lagging?!?!

 

intel seem to have a lot of trouble with thier throteling tubo boost and etc feature since the core architecture -.-

lucky for us most of the time only disabeling thoses feature solve the problem

 

Er, it might but I doubt it..

It's to do with CPU core-parking guys.. It stops the machine being sluggish because of the way it shifts around threads and also parks cores.. Now, it doesn't park cores so the switching threads activity doesn't slow the machine down. Something like that.

 

Anyone else want to test this out?

 

This has fixed it for me, now getting proper performance and responsiveness with EIST and Turbo still enabled.. Definitely an improvement!

 

i read that as a fix for the touchpad...my bad

 

You can always change it back by setting the valuemax back to 100

It might work, I don't know. Let us know if it does! I had uninstalled the synaptics driver and rarely use the TP anyway..

 

did it , thanks pras. touchpad does feel a little better but not sure cause i don't really use it that often, hahhah

 

aaaaaaay!! nice one, i find the whole system is more responsive, noticeable initially via the mouse pointer itself, but also getting slightly higher performance

 

Awesome find....I'm ready to get home & test this out.

 

same here...cant wait to test it....awesome tweak...

 

Good find man, +1 rep!

 

Nice Tip.

Performance seems about the same for me.

+1 for the info.

 

nice one.
i found 3 places in the registry that needed changing too. though the third one which was the 'currentcontrolset' had already a 0 value. also my original value was 64...though it shows 100 in brackets.

 

Yes, I had the same experience..

64 is 100 in Hexadecimal (Base 16 - google it if you are interested)

 

oh ok that makes sense. thanks for clearing that up.

 

Thank you Mr. Pras has made this thing snappy awesome find will rep when allowed.

checked cpuid and the max Ghz is 3.192 and its rated to go up to 3.3 hmmmmmm

 

Great!! I'm loving it too, awesome that it works for you too!

I found it at
http://ultimatecomputers.net/forum/viewtopic.php?f=7&t=3644

 

Good heavens--- this needs to be a sticky, I cannot believe how much smoother games are, it was like a free CPU upgrade! I'd give you a +5 rep if I could! Thanks Mr Pras!

PS: Your avatar disturbs me though

 

Would this fix help Core Duo's? And my m11x?

 

try it its worth looking into if it helps only with keeping your cores unparked.

 

From original source:

Who is affected

"It only applies to Windows 7 X64 and X32 and only in systems using more than 2 physicial CPU's and/or more than 2 "logical" cores - ie: Core i7's."

 

This is an amazing fix and worked wonders for my i7 Desktop in certain games i would see some nasty stuttering...All gone now... thank you + Rep ...

 

Thanks Mr Pras for the tweak

Works perfect !

 

Just curious,

Did this increase anyone's temps after the hack?

Seems like they would increase, as the cores are no longer in a lower power state.

 

Noob question here:

How do I find/search for more keys?
Does a full shut down, power off, and cold restart mean turn laptop off and then just restart?

Thanks.

 

Nope. Just do the initial search of the key. Once you see the ValueMax change it to 0. Then press F3 and it will do the search of same key again. You will see two more ValueMax values, change them to zero and then you are done

 

Great find! +1

 

i vote that this should be moved to a sticky in the windows forum. helped out with my np8760 quite a bit.

 

hey i found only two instances...is that a problem?....everyone seems to find three instances of that key....

 

Thanks for the info, can't wait to try on my desktop i7.

+rep, ofc.

 

Just went through the Core Parking / Intelligent Timer Tick / Timer Coalescing article. My question is:

1) In the event where; core 0 is in max turbo boost / core 0 & 1 is in turbo boost, does the remaining cores need to be in a parked state to channel all available voltage?

2) If all cores are constantly active, will core 0 be able to max turbo boost in single core processes?

Looks like benching in both environments with both single process and multi-process benchmark will show the answer. I will see if i can post some results over the weekend. If anybody can post results sooner, I'm sure we will all be happy to see some real numbers.

+rep for wonderful idea.

 

What's the affect on heat/battery life/power consumption?

 

It's related to power profiles (usually there are 3) perhaps you only have two?

 

I guess that there is a minimal increase in heat and probably a small reduction in battery life. Core parking is an aggressive power saving function that must have some value in terms of lowering power consumption. So there will be some disadvantage, probably minor.

I've used the computer on battery with this hack and it is pretty similar, in fact I didn't notice any real-world difference. Perhaps in a series of power benches you could see a difference, personally I'd rather have a snappy machine and lose a few minutes of battery life

Nearly all my benches so far are increased in the order of around 1%.

Remember that 1% in a bench doesn't mean 1% increase in performance. The measured increase is due to less "Stalls" from the CPU because it's not parking and unparking the cores. Although it looks like only a minor increase, it's caused by a decrease in latency so in that case 1% is actually a significant improvement.

It's great that this fix works for all i7 Win7 machines (and i5 too)

Perhaps the title should be changed to "Fix for Win7 sluggish multi-core performance"

Just noticed the move - thank you mods!!!

 

Mr. Pras great find indeed will look forward to the next awesome find

 

you guys, especially the ones who are in love with cut and paste from other web sites, do know that all of this can be controlled from the command line without having to resort to ill-informed and mis-understood direct editing of multiple registry values.

powercfg /qh scheme_current sub_processor will get you started.

Identify the GUIDs of the power plans you want to change and then look for the AC and DC values needed. If you REALLY REALLY want/need to disable parking, the values need to be set to 0. It's usually 4 (not two or three as some rocket scientist here found) values per power plan; there are AC and DC settings for max cores plus another set of AC and DC settings for min cores. All 4 of the min/max/ac/dc settings should be changed in sync according to the msft documentation on the subject. The default values for the min core ac/dc settings is generally 0a while the ac/dc settings for max core is 64.

So you will be writing a batch file with FOUR powercfg entries plus a fifth to make the just changed power plan current.

Or, set up a new power plan, edit the ac/dc/min/max core values ONCE, then switch into that power plan as needed.

It's probably a good idea to create a NEW power plan with the munged parking settings and just switch to that plan when wanted/needed. This leaves you the option of going back to a known-good power plan if you've screwed something up.

For you modern savages who are able to read and comprehend freely available documentation instead of clipping partial/incorrect info from other web sites, powercfg is well documented on technet.

doing things properly and easily isn't as spectacular as (oooh, ahhh) 'registry hacks', but it's a lot safer.........

 

never said it was and please don't judge people for calling these registry changes, hacks(personally i looked for something to have a snappier machine this is the only viable solution i've found). don't get me wrong this is no hack just a modification in the registry on current power plans.

 

Wouldn't Core 2 Quads also be affected then?

 

i don't believe so but since they have more than 2 cores it could give it a try if possible.

 

regardless of the machine/cpu you're on, running

powercfg /qh scheme_current sub_processor

will tell you what kind of sub_processor values can be set for your power plans. And it will tell you ALL of them without manually hunting through the registry.

 

newsposter,

Great info.

Thanks and +1 for the tips.

 

Thanks for the extra info.

I think it's unnecessary to complain about copying and pasting (I'm just sharing something I found) and also about the methods. Changing the registry in the way offered is a valid way of stopping core-parking (as seen by our experiences here) and is much easier than the method you describe.

It's great that you have info to share, but clearly people are getting something out of the info I copied and pasted, so where's the harm?

Personally I found that "manually" searching through the registry took a few seconds and worked fine! It's much easier for noobs to change the settings that way and isn't difficult at all. Putting in a value and searching for it is actually easier than the method you are suggesting.

I also read in your comment about changing the settings back - it's way easier to just search like in the first instance and change the valuemax back to 64.

No-one is in love with posting from other sites, this is the first time I've done that here so please curtail your attitude.

Ill-informed and misunderstood is also not really true. It works and is a direct change to the powerplan specific to core parking. Nothing wrong with it.

If you have a better solution, please share it. Your description of the powerplan does not make things easier for noobs. Changing the values in the registry is definitely easier even if it's not technically the best way to do it, who cares?

 

a missed keystroke while running powercfg will result in a 'bad command' and no harm done.

a missed keystroke while manually editing the registry can easily mess a system up to the point of becoming unbootable.

your ball......

 

By what you say here, I have to assume that you are the one who wrote the code or did the documentation for this and that you work for Microsoft.
Otherwise you are also copy pasting from somewhere/someone else. Right?

I thank both you and Mr Pras for the useful info and I appreciate the fact that you provided us with two different ways to achieve the same thing.

Let people decide what's more convenient and what works best for them.
For those who play with the settings and the registry you always have to keep a backup or create a restore point prior to that.

 

Thanks for this. Can't believe i missed this before!

This tweak kinda help with a problem i've been having.

Thanks again.
Ned.

 

Ok so this for Laptop Core4 i7's, and not desktop i7's.
So no worries.