What is sysmain, and why does it sometimes use a bunch of CPU? Can I disable it, and what happens if I do?

Hi Aden,

I am John J.D., a fellow Microsoft user like you.

SysMain is a built-in Windows service that helps improve the performance of your PC by preloading frequently used apps in your RAM. It analyzes your PC usage to predict which apps you're likely to use and preloads them, allowing for quicker app launches.

If you're concerned about the CPU usage, disabling SysMain is an option. However, it's important to note that disabling it may negatively impact system performance. It's generally recommended to leave SysMain enabled as it works to optimize your PC's performance. You can find instructions on how to disable it in the Services window or through the Command Prompt, but it's best to keep the default settings for optimal performance. https://www.thewindowsclub.com/disable-superfet...

Please let me know if you have any further questions or concerns. Let's work together to resolve the issue.

Best regards,

John J.D.

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You need more RAM. You have 4GB but Windows works much better with a minimum of 8GB. A long while ago, 4GB would have been sufficient for your use, but with subsequent updates adding more and more functionality and security updates to Windows, 4GB might not cut it any more.

It sounds like you've had your computer for a while, and this is good, but it is possible that your User Profile has gotten to be quite large. When you log onto your computer, your User Profile is loaded up. Your Profile stores information about your logon, including websites you've browsed. Images you've come across in your web browsing is also stored. Your Profile can become quite large and this can slow down your computer, especially if it is operating on 4GB of RAM.

Try the following steps:

1. Download and run a program called ccleaner. On its defaults, it can clean up much of your User Profile and lots of other stuff that can slow your computer down.

That step alone might be enough to speed up your computer.

2. Get some help to see if your computer can be upgraded to 8GB of RAM, RAM is relatively cheap as an upgrade and your computer would literally feel twice as fast!

Hope that helps...

I am not very technical but if my SysMain is using 96 percent of my CPU, how can it be optimizing my conputer. I have a small HP All in One with I think 4MB of Ram (maybe GB) and it is running so slow as to be unusable. It happened very suddenly, right after a MS update. I think the update reset something and now my computer is not useful to me. If I disable SysMain to see if it works better again, then would it be bad to leave it disabled? I dont do a lot of heavy computing or games or anything. Mostly correspondence and reading email. Do I need professional help?

Good morning,

Sorry if I don't write correctly, I use Google translate, because I don't speak English.

I have a question, many people say that for an nvme hard drive like mine (7350 writes, 6000 reads), it is better to disable SysMain, because my hard drive is faster than my ram (4000Mhz).

Is this true or false?

Good day.

Well, Hard Drives are surely slow, so sysmain enabled is good if you have high ram, the point is if you have low ram then disabling sysmain is a must.

Let me help you by clearing something

Even if you buy the fastest available ssd ever manufactured its still slower than a ram

the 4000Mhz you are referring is 4000million transfers in a sec which is a huge bandwidth compared to even your 6000MBps ssd

I hope this helps with your confusion my friend