Windows 10: SysMain Causing High Disk or High CPU Usage? Here’s How to Disable It


The October update of Windows 10 pulled a move on us, those who had disabled Superfetch in Windows 10 because it was slowing down our computer with its high disk usage.

Starting now, it has been replaced with SysMain, which is basically exactly the same thing but under a new name.

And, of course, it soon started to act up on my computer. I knew I had disabled Superfetch and I was shocked to see this new thing called SysMain eating up my disk space and slowing down my computer to a state that made it unresponsive and extremely annoying. Fortunately, you can disable SysMain in Windows 10 and I will show you how to do it.

But first things first…

What is SysMain and should you disable it?

Basically, SysMain is the same thing as Superfetch, but with a different name. What this service does it analyzes your computer usage patterns and optimizes app launching and programs on your computer.

But the problem is that, for most people, SysMain starts using up too many resources, showing high disk usage and slowing down your computer to unbearable levels.

I personally went through this for a few days before completely losing it and starting to investigate the culprit (I initially thought it was the Windows Update downloader that was slowing me down, but it was SysMain).

In other cases, SysMain ends up eating up all your CPU power, not the disk… but in the end, it doesn’t really matter what it does because the result is the same: your computer is slower instead of faster as the SysMain service claims to make it.

So… should you disable SysMain in Windows 10? Unless you’re having no problems with it (yet), I see no reason why you wouldn’t disable it.

There’s no noticeable difference in speed on my computer with it activated or deactivated… the only difference is that I no longer have to endure it slowing down my computer in the morning when I start working.

So yes, if it is causing you problems, don’t hesitate to disable SysMain and fix your high disk usage or high CPU usage following the guide below!

How to disable SysMain?

This is easily done: first, press the Windows key and R and then type, in the new window that appears, services.msc

Now you’re taken to a screen that shows you all the services on your system (running, stopped or disabled) and it’s usually a good idea not to mess up with them unless you really know what you’re doing.

In this case, you are trying to disable SysMain which is safe to do and will actually help you speed up your computer or laptop if it’s causing problems.

In the Services(local) category, scroll down the list until you find the entry titled SysMain, as seen below:

Right click it and select “Properties” to be take to its properties menu:

From there, first click the “Stop” button towards the bottom, where it says “Service status: Running”, then from the menu above, at the Startup type, select “Disabled” instead of Automatic:

Finally, click Apply and OK and you’re all set! The SysMain service is both stopped and it will no longer launch on Startup.

Now you have disabled SysMain in Windows 10 and you should no longer have performance issues related to it. It might reactivate at a later date (usually after a new Windows 10 update) but if it does, you know now how to disable it to regain control over your computer’s performance.

And this is it! I hope you found our guide useful and that it’s going to save you a lot of time in the future, now that you know how to disable SysMain in Windows.


  1. I presume that SysMain has a positive value and that there’s a penalty for turning it off (haven’t read all the b/g so apologies if this is in there) – is there a way to either throttle it back a bit or at least de-prioritize it? It’s frustrating to wake up my laptop 5 minutes before a meeting and not be able to join the meeting on time because Windows is busy doing what’s really a housekeeping activity.


  2. Ugh thanks Microsoft again for this, Was watching it access files all across my drives was no rime or reason, just seemed to be causing lots of access slows and interrupt request while I was doing anything. all it seems to do is run up the mtbf counter lol. thanks again Microsoft same sh** different name doing nothing helpful.
    Thanks for clarifying what this was.

  3. This was an evil demon in my computer. I called for an exorcist to come and expel it from my once-beautiful machine. With the help of Christ Jesus, it it now gone, burning in the depths of hell from which is came.

  4. Thanks! What a difference! I have been planning to do this for awhile, but ended up trying other options first. I work from home and all sudden my accounting software slowed down to a crawl, then computer locks up. Also happened when playing games in the evening. I finally tried short time ago.

  5. Ah… so they changed its name. Why do i get the feeling they changed its name to SysMain to make it sound imposing, to the average user, and super, super important and must never ever be switched off or else bad things will happen? Or is that just me being dramatic again?
    Anyway, thank you 🙂

  6. Thanks for this. My computer is now usable. Used to have to turn it on an hour before I needed it, and then, if it got upset, it would revert to being useless sludge for no reason clear to me.
    I may even have replaced my previous laptop because it was too slow, when it might have been a previous incarnation of the same problem.
    Microsoft should put out a fix.

    • I was using Firefox and it was eating up a ton of resources. Switched to Chrome recently and things got fixed. So maybe consider trying a different browser, at least to see if it makes a difference.

  7. So very weird, when you are on task manager (not idle) on the performance tab you can see something starts using the cpu, switch to the details tab and the process cpu usage becomes zero.
    Took me a while to catch the pid and find out the culprit.

  8. Yes, I did it. I killed Superfetch. I hated it so much, it…it…it… flames… flames, on the sides of my face, breathing…breathless…heaping … AND THOSE BASTARDS RENAMED IT?!!! Thank you for the lovely write up that has made all my dreams of not needing to buy a new laptop come true all over again 🙂

  9. excellent advice, I am always worried to follow people’s advice like this, most of them not trustworthy.
    thank you for the simple (jargon free) advice that works

  10. After an hour of Youtube, 15 reboots, this, that, and the other thing, it was YOU who managed to uncover the culprit and reign in the best from 100% back to 2%! Thank you so much, man~ Life safer.

  11. And when i thought Superfetch had made a comeback out of hell… IT REALLY DID but under a new name!! Damn man, that thing hogged my PC for at least 3 months before. glad this time i was aware of microsoft hogwares and searched for this solution and found it simple and fast here. Thank you very much.

  12. Aha! I opened this page, decided to go ahead, turned back to the computer and – it had all gone! Disk usage down to 0%, all’s right with the world.
    It’s psychic.

  13. My Win10 quad-core laptop was getting so slow it felt like an old 286 on dial-up. Complained repeatedly to corp IT who are ‘studying it’. Near term solution was to re-image my drive….so, now I have ‘the latest’ version of Win10 🙂 So after all the updates and preliminaries, I open Task Manager and… 100% disk usage still 🙁 ! with SysMain at the top of the list. Thank you for the posting on the name change.
    It’s a corporate unit else I would be running Ubuntu Linux.


    My laptop is actually possible to use again. Can’t thank you profoundly enough – was close to trying a drive wipe and reinstall trying to get the wretched thing to quit taking upwards of ten seconds to respond to keyboard inputs and hanging for 30sec to over a minute every five to ten minutes. I’d all but convinced myself it was undetectably virused.

    Why in Babbage’s name do Microsoft insist on this sort of utterly broken ‘feature’?

    • I honestly considered switching to Linux after all this mess-up, but there are so many Windows programs (ahem… games… ahem) that I can’t run in Linux so we’re sticking with them and finding solutions to their mess. Happy to help!

  15. Really a mess. Thanks a lot for giving a solution. I might be needing help on another problem that is eating my CPU and memory. I dont know how but wup.exe is in my system. It a trojan virus. I have searched a lot on how to remove it. But solution actually came up.

    I end the task from task manager and then also deleted from c disk but then again after 5minutes it came back. If you can help me on removing it. I will be really greatful.

    • I am not familiar with that, but if it is a virus or trojan, you should try installing a free antivirus software, get rid of the virus and uninstall the antivirus (if you think you don’t need it or you want your computer to run faster).

  16. Well I thought that would be too easy. Once you click in the start area, StartMenuExperienceHost.exe launches. I’m sure that can be disabled but before I change the name to .old, has anyone done this? It has explicit permissions for TrustedInstaller as the ONLY full access user…

  17. you might have just saved me a crap ton of pulling my hair out and may have saved a hdds life today lol cheers mayte

  18. this worked amazing like i went 99% to 3%.. thank you so much. i hope stopping this service does not make any issues in the long run or cause any other issue. thank you…

  19. Thank you!! I was beginning to think I needed to upgrade and get a new computer, but not now! Went from 65% usage to 2%!

  20. Interesting, normally the Superfetch / Sysmain service should actually improve file performance, and not make it worse. I guess Microsoft f-cked up by not setting a very low I/O priority on their process. Maybe they forgot it when they renamed the service for no good reason. Thankfully, with open source task managers like ProcessHacker, it works to enforce a low I/O priority on that certain svchost process. So if it’s no big hassle for someone, this is the better alternative compared to disabling the service completely.

  21. I stopped SysMain and the disk usage went from 90% to 1%. So far, I haven’t had any adverse effect on my system. Thanks!

  22. Words cannot capture the frustration the 100% disc usage has caused and how long I’ve chased it. There are no words to adequately express my THANKFULNESS for this post. You gave me my PC back.

    THANK YOU!!!

  23. I do it step by step as you said and i disabled it, now the usage of disk is 10-12%.
    But whenever i start using Adobe After Effects / Premiere Pro for making videos and rendering it, the hard disk shows 99% of the usage.
    I think it should be eating RAM not Hard disk.
    So what i did- i started Rendering my Videos in Media Encoder, for few minutes its normal around 20-30% of disk and my RAM uses 70% and a couple of minutes it goes up to 99% disk AGAIN.

    I had to change my hard disk because I found out that the disk health was 9% so had to replace it and got a new one. I don’t understand the same thing is repeated here and I am afraid that I might have to buy a new one.

    Can anyone help with this issue. Its Pissing me off!

  24. I thought I got a really bad virus. Maybe because I’ve been watching videos of someone exposing viruses lately, but 100% disc usage would probably freak most people out. This saved my life!

  25. omg thx bro 100 disk right now i have only 1-2 thx brooooooooooooo i love ypu <3 (no bot or somthing i have discord no bib bip bip :))) thx)

  26. This fixed Everything !!!
    Was looking for a fix on some spikes of lag that I experienced during photo-editing, very annoying. So I disabled Sysmain after finding this article:
    It has literally, instantly, right on the spot, fixed Everything!
    My computer is fast again, no problems opening up tabs and files taking ages to load, games start up instantly, even youtube movies play instantly, it’s insane.
    Thank you very much for sharing and google for letting me find this, and everyone that is reading for reading this, thanks to you all! And beers on me if you’re in Amsterdam!!


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.