Okay, I've been too embarrassed to ask this before, but I'm going to put on my tin foil hat now, extra large, double tin, and ask now.

Why do some processes/services stop just because I open Task Manager?

Now the question itself doesn't require any tin foil hat because this is FACT. Every time I open task manager, it shows CPU usage over 80%, then immediately goes down and stays there. I close Task Manager, wait 1 second, open it back up, and back to huge CPU usage with usually one process showing in orange. Then, again, immediately goes down to 1 or 2 or 3 percent. Close task manager, open it again, and... rinse and repeat.

If it's an essential "service" or "process" then why wouldn't it keep working despite Task Manager being open? I look every time, and while Task Manager itself is listed under usage, it's ALWAYS only 1 or 2 percent. No, the ones that come up big and highlighted are always these: Gaming Services (despite the fact I have Game Mode (and thus X-Box gaming bar disabled), Runtime broker, and Start.

I can leave Task Manager open for hours and the CPU usage never rises above 5 or 10 percent. Close it, immediately open it back up and boom, gaming services, start, or runtime broker (often times two of gaming services and runtime broker) are at the top of the list when sorting by CPU usage and usually one in orange and very high.

Okay, all of what I've listed is fact, for me, on this computer. Now for the tin foil hat part. If something is essential, it shouldn't matter if task manager is open on the screen or not, it should be running if it's essential. I can't help but wonder if it's nefarious, and "hiding" when task manager is open.

Okay, tin foil hat off now.

But seriously, why the fuck does having the Task Manager window open stop some processes/services?

ADDED: The reason I'm concerned is, I often, in game (any game) see massive performance drops. I leave game, open task manager to see wtf is going on, and see what I described above, go back in game, massive performance drop, leave, check task manager, same as above. I leave Task Manager window open, go back in game, and smoooooth as butter.

Again. What the bloody fuck is going on?

ADDED2: Oh, I have run about a hundred malware scans, both online and offline. Haven't seen anything there yet.

The CPU jumps to 80% because it's working to open the task manager.
Some processes that are running in the background stop even if you move the mouse, like routine optimizations.

Sorry, I don't buy that because Task Manager itself has it's own line showing it's CPU usage. That seems to me like saying if you open up Excel whatever resources it's using would show up under, I dunno, Gaming Services. What does Gaming Services (the one listed at the top most of the time) have to do with opening task manager.

I get that the optimization processes (file index, disk optimization, etc) stop when doing ANYTHING. But your answer doesn't explain why in game performance drops massively, then when I leave task manager open gaming performance is great. This isn't always the case, but it is often the case. I have, on occasion, played an entire day leaving Task Manager open because every time I closed it the game just didn't run well.

So, I just closed Firefox after posting that last post. Opened task manager three different times. All three times Gaming Services was listed at the top, in orange, with CPU usage over 75%.

I just don't believe that opening task manager makes gaming services suddenly require 70% CPU usage.

You can use Process Explorer or Process Monitor by Sysinternals to monitor all the stuff and check if there's any service that stops when Windows task manager is open. Those are very lightweight programs that don't need installation.
Let me dig a link

Edit: https://learn.microsoft.com/en-us/sysinternals/downloads/procmon

https://learn.microsoft.com/en-us/sysinternals/downloads/process-explorer

Download button on the bottom of the page.

Gee, you don't need to go to all of that trouble, I can search those programs myself. I appreciate it, but I didn't mean to impose anything other than asking for thoughts on the issue.

And thanks for those suggestions. Very appreciated.

Just tested it and for me task manager does use a load of resources for a very brief time. Got a screen shot of it using 29%

About 1/4 of a second earlier the total CPU usage was at 80%

Personally I can see task manager taking that much resources

Firstly, Task Manager runs at the highest priority, it need to in order to kill hung processes. This means when it asks for processor time it will get it and get it fast.

Second, on opening it must pool a list of every process running and its memory allocation. Normally there's about 200+ processes running

Lastly, I'm guessing it takes a moment to plot activity over time

Yet again, if it's just a matter of opening task manager, then I wouldn't be seeing massive performance drops in a game. I'm not opening up task manager while playing. Again, I have days where the only way I could play a game was to leave task manager open all day.

Wireshark can monitor your net traffic if you are interested. It is not a simple tool but not super complicated either.

Game bar sounds super suspicious but seems to be just another resource hog from Microsoft.

Yeah, and I really don't get why Gaming Services (often two of them) show up as processes at all, much less the biggest one with over 70% CPU usage when I have disabled every option there is under Gaming in settings. (screenshot)

I've read that malware is doing it to hide it's presence.
Had the same system's behaviour (fresh install, so it's not malware), but i wasn't gaming - system was idle. Windows 11 tried to find something on my old HDD (disk indexing turned off). Looks like NSA found nothing of interest and left me alone. Or maybe removal of XBox Game Bar through powershell command and installation of a more recent version of it through Microsoft Store helped. Now even when PC is idle, there is no noticeable HDD activity.
I also used ShutUP10 program (safe, recommended settings) - maybe it did the trick as well.

And you can try this, if you didn't. Microsoft is using other people's PCs for "Delivery Optimization", maybe that is hogging your CPU. Why buy servers, when you can load other people's PCs, right?

Talking about tin foil hat: anyone noticed absense of HDD activity led on currently sold PC chassis from western manufacturers? There is only "Power led" now! :P

PS: if it was bothering me so much, i'd just reinstall Windows (from official, non-tampered/modified/hacked iso) and drivers. Then used something like Clonezilla or "Acronis for Western Digital" (if you have a WD drive, they give 5-year license) to create an image of the system to restore PC to this state in 10 minutes in future. Heard good things about Macrium Reflect (fast, protects images from ransomware), but didn't tried it myself. XBox Game Bar is something like Steam overlay for Windows. You can easily record videos/screenshots from games, chat with friends, setup your gamepad, monitor system resources (limited, compared to tools like MSI Afterburner), etc.

You can use Resource Monitor to Suspend Gaming Services. Just load it, find the process, right click it and suspend that process, it should stay suspended after restart. From my experience, it will get unsuspended after a windows update, after a crash, or if windows was not shut down properly.

The more aggressive method would be to completley remove/uninstall all the xbox elements from your PC, mostly using Windows Powershell:

https://www.systweak.com/blogs/how-to-remove-bloatware-from-windows-11/

For anyone to be able to offer relevant advice, you need to post more information about your system setup. What hardware are you using? Which version of Windows? (and is it 32- or 64-bit). Given the nature of your question a list of the processes you have running would also be very useful.

So the following is just guesswork - but given the symptoms you describe, I would speculate that the issue is related to the security software you have installed (so please list this also). When Task Manager starts, it enumerates all your processes and this could be triggering security software to do an extra scan of certain ones. Alternatively, a lot of security software operate by setting "hooks" within Windows, particularly in the file system so they are triggered on every file access. If a hook is triggered by another process, it is possible for that hook's CPU activity to be attributed to that process, rather than the security software itself (if you were running a full-screen game and then Alt-Tabbed to Task Manager, the game would be minimised which can be a complicated process).

Another possibility is if you were running multiple anti-virus (AV) scanners with background checking enabled. Doing this is bad since each scanner, when doing a scan, has to access its own files (program code, signature databases) which will in turn trigger any other scanners - this could result in a never-ending loop (which will actually terminate in a BSOD), a long delay while you're having a file scan jambouree or may work in the (generally unlikely) case where one AV provider has coded its engine to tip-toe around all the others. This can happen if you have installed multiple AVs (duh) but might also occur if you uninstalled one and the uninstaller didn't do its job properly.

Norton used to be infamous for this, but the current front runner seems to be McAfee.

See the discussion thread at https://www.wilderssecurity.com/threads/question-about-mcafee.451361
(which this forum's software seems to persist in munging). Process Explorer is a good choice to see what is going on, but I would also suggest Process Hacker - it is a very similar tool, but has more options and useful tools - in this case the ability to add a column for "Total I/O" (Process Explorer allows you to show Disk Reads and Writes in separate columns but not to aggregate them). Were these figures obtained using one of the other tools above, or did you read them from Task Manager itself? When Task Manager starts, it doesn't know what constitutes 100% CPU so it has to calibrate itself in a way that works for all processors (including ones not yet released, ruling out any lookup tables for specific CPUs) and it appears to do so by generating maximum CPU usage for an instant on startup. This then tells it (in terms of number of ticks or instructions per second) what the CPU can manage, which then allows it to calculate percentages for every other process. Since this only happens for an instant, it will register as less than (usually far less) 100% on other process monitors which show CPU usage averaged over a second or so. If you have 200+ background processes then your system would very likely benefit from a cleanup. I have 27 processes running including 2 browsers, 3 proxies (two for filtering, one for anonymisation) and three types of security software. This may have been an issue back in the days of 2-4Mhz 6502 or Z80 8-bit processors, but hardly likely to be one now - even with a really creaky system.

Oh, and one more thing, the task manager is the nearest thing Windows has to a secure attention mode/magic system request.

I was including 100ish Windows services in with that (and over estimated)

Currently have 60 BG processes running

12 are nVidia
8 bloody keyboard and mouse drivers. I could not use them, but then both keyboard and mouse does a pulsating unicorn vomit of RBG