Are you rendering in the background, ie. not leaving Vegas as the active foreground application? And do you have one or more than one monitors?

Don't have Alder Lake but definitely never experienced that myself with Win11. I don't think Win11 has any settings to adjust core affinity. But I do that myself in my Asus bios. To give higher priority to the cooler running cores which keeps the overall clock rate up. I use a utility called CoreTemp to id the hotheads.

You might want to play around a little with Win11 gpu scheduling and app-specific settings for gpu preference under System/Display/Graphics and see if they affect the situation.

Are you rendering in the background, ie. not leaving Vegas as the active foreground application? And do you have one or more than one monitors?

@daniel-t

It does not matter focused foreground or minimized (I already tried it) since I was reading up on the internet on such issues regarding the windows 11 scheduler preferring the (slower) e-cores when minimizing your render app.

Anyway, according to (again the internet ...) it could be avoided by setting your power mode to "Best Performance". This did not help (perhaps because my issue is something else anyway, having a tunnel vision on an issue is often wrong).

I am also experimenting with turning the E-cores off to park (using Gigabytes tool for fixing DRM game issue)

(Some legacy games - even a few new ones- with DRM protection - have an issue with E-cores thinking your system is another PC)

I also have BIOS setting to park the e-cores on the fly called 'Legacy Game Compatibility Mode', but that is triggered by a scroll lock key on my keyboard; unfortunately, I do not have a warning led on that key, and <I do not want to park my e-cores by accidently hitting that key and not noticing it 😬

@Howard-Vigorita I checked the all the core temperatures, there is no individual hot-head.

So the search goes on. I need to get to the bottom of this, I can live with the task manger running whenever I render as a workaround to render 2x faster, but this is too crazy to leave alone, it almost seems Vegas with that render benchmark project is not taxing my system enough to get fully going as if there is some threshold that needs to be crossed by some other app like the task manager.

I did notice that once Vegas and task manager are concurrently running while rendering, I am rendering fast, and afterwards you can get rid of the task manager and the rendering keeps being fast as long as you do not end Vegas. Starting up Vegas again after you killed or ended it normally will get me back in slow rendering...

I am getting a clearer view of what is going on. It is definitely the E-core vs P-core usage (on alder lake processors) with windows 11 (probably worse on windows 10 - but I cannot test that) I was guessing intuitively in the first place. I got some proof now, disabling the E-cores (putting them to park via the Gigabyte DRM fix tool), will yield faster rendering (almost 2x faster on intel QSV or NVENC rendering), pure processor rendering (non QSV, non NVENC) also is faster, more like 1.5x faster. I assume the effect of having the task monitor active concurrently without disabling E-cores has pretty much the same effect as the windows task monitor will be likely be handled by the E-cores, thus effectively blocking Vegas from using them which in turn has the side effect of faster rendering since Vegas is then obviously using more often the P-cores...

I don't see this issue on my 12700K with Windows 11 Pro running 8 P cores @5.2, 6 cores @5.3, 3 cores @5.4. E cores set @4.1ghz. For my own experience and my workflow. I see that my system rendering 4K footage very fast, like I was rendering 1080P. This is with Asrock 6900XT OC Edition card.

@bitman you might want to double check is that resizable bar is enabled in bios... probably is if you're running win11... I think both ms and nvidia recommend that.

@BruceUSA My processor has 4 more E-cores, so maybe the chance Windows 11 Thread Director is picking E-cores in my system is greater and could lead to my system being less performing than yours. Do you set your cores to certain speeds in BIOS or do you let the system choose? Anyway, my issue is perfectly reproducible, and I am pretty sure I can rule out culprits such as memory, graphic card, motherboard, and SSD.

Can you do some render tests disabling E-cores vs enabling?

@Howard-Vigorita Indeed I remember reading up on that last winter building my sons PC, I need to follow up on that and experiment with this as it is currently not enabled according the NVIDEA control panel. Good idea. I assume it will not fix P-core E-core issue of this post, but it can improve graphic speeds.

@BruceUSA My processor has 4 more E-cores, so maybe the chance Windows 11 Thread Director is picking E-cores in my system is greater and could lead to my system being less performing than yours. Do you set your cores to certain speeds in BIOS or do you let the system choose? Anyway, my issue is perfectly reproducible, and I am pretty sure I can rule out culprits such as memory, graphic card, motherboard, and SSD.

Can you do some render tests disabling E-cores vs enabling?

I set set all E Cores full speed @4.1ghz in the bios. This is manual overclocked. Full specs in my sig.

 

I set set all E Cores full speed @4.1ghz in the bios. This is manual overclocked. Full specs in my sig.

@BruceUSA do you have the same ability as the other user to turn off your e cores with a button press?

It would be interesting to see the difference between a CPU encode with and without e cores

Todd-b.

I am not sure how that is done with a button press to disable e cores. I am sure it can be done in the bios. If I find the free time I will give that a try to see what is the difference between CPU encode without the e cores. They are people on this forum own 12th gen CPU as well can give that a interesting finding also.

I found a solution that works without disabling the E-cores by enforcing Vegas to use Process threads only on the P-cores. That I consider a better solution for the Vegas slow rendering issue on Alder Lake than disabling the E-cores all together. With this solution other concurrent programs can still use threads on the E-cores.

This is how to do it:

1) Make a copy of your shortcut to Vegas.exe on your desktop (e.g., via copy paste) so you still have your original shortcut safe

2) Determine which and how many P-cores you want to allow for Vegas. For example, my alder Lake i9-12900K has 8 real cores (split into 16 virtual with hyperthreading active) which are counted from first core = 0 up to 15, (core 16-23 are the E-cores). To allow Vegas to use all my 16 virtual P cores and disallow Vegas to use E-cores, you need start Vegas with an affinity option bitmap, this bitmap holds which cores Vegas can use. It is expressed in HEX number rather than decimal:

The affinity must be set to HEX "FFFF" for the first 16 cores (cores 0 to 15)

for example, setting cores 0, 1, 2, 3 you set decimal "1+2+4+8" = decimal "15" = HEX "F"

3) open the properties tab of the copied shortcut and change the contends of the target field to

%ComSpec% /C Start /Normal /Affinity 0xFFFF vegas200.exe

4) That is all, just start Vegas from your new shortcut and enjoy faster rendering and edit.

5) You can check your Vegas core affinity in the task manager

@bitman

In ancient times, when my i7-6850K was fresh and new, there was an app from intel to set processor affinity to the core(s) with the best performance. I tinkered with it then, but I abandoned the effort because the difference in cores was not worth all the effort. Now, with more profound differences in core performance, it appears that setting affinity to cores has real possibility for performance optimization.

Thank you for visiting this phenomenon.

Core affinity can be set in real time from the Task Manager, but it doesn't survive a reboot. It can be handy for carving out a place for a screen recorder to run.

Been trying to get away from running stuff under command shells with win11 so I adapted the @bitman shortcut approach to a PowerShell script and figured I'd bump the the priority up to high while I was at it... caution not to go above high else you'll have to reboot if Vegas hangs because I don't think TaskManager can stop a Realtime priority process. The affinity below is for my 6-core laptop to exclude inner cores #2 and #4 which really cook when I do benchmark renders. The Dell laptop doesn't have affinity/priority settings in bios so this may be one of the few ways to do it for me:

Start-Process -FilePath "C:\Program Files\VEGAS\VEGAS Pro 20.0\vegas200.exe"
Get-WmiObject Win32_process -filter 'name = "vegas200.exe"' | foreach-object { $_.SetPriority(128)}
ForEach($PROCESS in GET-PROCESS vegas200) { $PROCESS.ProcessorAffinity=0xCCF}

There was also a free utility around called Prio that allowed you to set Process Priority in Task Manager and save it across restarts and reboots. I used to use in back with vp16 on Win10 but don't know if it saves affinity settings and/or runs with win11.

edit: changed the hex affinity because Get-Process apparently takes the bits in backwards. Also named that script "startvp20.ps1" so it could be started by a direct shortcut to powershell which allows the VP20 icon to be applied to it rather than right-clicking on the ps1 to Run With Powershell. Here's the shortcut def I tried 1st:

target: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -File .\startvp20.ps1

start in: %~dp0

run: minimized

That funky "start in" tells the shortcut to switch to the folder where it finds the ps1 script which I threw on desktop next to the target shortcut. Then I moved it to my c:\util folder where I throw stuff like ffmpeg which I include my search path. Since it's on the search path, "-File startvp20.ps1" is the only change I had to make in the target. Run minimized hides the PowerShell screen while it flashes by briefly.

@Howard-Vigorita Thanks for the alternative way via PowerShell, you can add priority to the shortcut method as well, I did not want to up the priority together with the affinity as not to complicate and confuse my testing with too many changed variables at the same time.

Unfortunately, although setting Vegas to a certain core affinity via PowerShell method or directly via shortcut startup seems to be set correctly (as you can check in via the task manager), it does not give me (anymore) the desired result of 2x faster render, was it a fluke yesterday when it worked?

Wat does still work (to have the rendering 2x as fast) is turning the E-cores off to park completely (using Gigabytes tool for fixing DRM game issue) or quite often by running the task manager concurrently as in the original post...

Is windows 11 sometimes overruling the affinity set? Or is something else going on. Setting Vegas to use only the P-cores (aka affinity setting) should more or less have the same effect on rendering as turning off the E-cores for everyone, but it is not...

Investigation still ongoing...

I was seriously considering buying a 12900k processor. However, I did not like the division into P and E cores, I guessed that this would be a problem. Do I understand correctly that you turned the 16-core processor into an eight-core one with these experiments? Isn't older 10-core intel or 16-core Amd with P cores better for Vegas?

What is the difference when playing the benchmark project with E cores on and off?

 

What is the difference when playing the benchmark project with E cores on and off?

It's the obvious question, so far, nobody wants to test that. I would do a AVC transcode to MagixAVC (mainconcept) . A CPU render is where there should be some advantage to having the e cores even if they';re not very useful otherwise (for a desktop computer)

I just did a fresh Vegas install to a new Zenbook laptop: 12900h / 3060 gpu / IrisXe igpu. The bios has no core settings so I couldn't test that. Render times of Sample Project to 1080p were a big improvement over my old Dell xps15 but were relatively unchanged by anything I did raising priority or manipulating core-affinity via Task Manager. Except the MainConcept render time increased by 10 seconds if I messed with core-affinity for Vegas.

xps15: Nvenc: 1:41; Qsv: 1:40; MC: 2:21

Zenbook: Nvenc: 0:52; Qsv: 0:52; MC: 0:57

If I limited Vegas to p-cores on the Zenbook, MC render time was 1:07. Note that the 12900h mobile cpu is a little different from the 12900k desktop... only 6 p-cores, 2-treads each + 8 e-cores, 1 thread each. Total 20 threads: 12 p-core + 8 e-core. p-cores can boost to 5ghz but e-cores only boost to 3.8 ghz.

@Howard-Vigorita When you do a transcode from AVC 420 to AVC 420 mainconcept do you get 100% CPU including 100% load of E cores?

The following is 1080P AVC to 1080P Mainconcept AVC and it's what you expect to see with conventional CPU's

Looks similar for the p-cores but the e-cores are the bottom 8 logical processors, and they look a little lower than the p-cores... I think the p-cores are on the perimeter of the cpu and can run at a higher clock because they have a better ability to dissipate heat than the inner cores. If the inner cores overheated, they would heat up all the cores and lead to a general slowdown.

@Howard-Vigorita That looks good, E cores not creating latency for P cores reducing effective power, instead 100% P cores +additional E core processing power. I wondered how that would work in a multithreaded workload like a CPU encode.