Service Host SysMain Causing High Disk Usage? – Best Solution

In October 2018, Microsoft updated its Windows 10 Operating System, where they replaced Superfetch with Service Host SysMain Causing High Disk Usage.

Some people used to disable Superfetch because it used to slow the computer down. It used to use high disk space which used to create the issue.

However, SysMain is no different from Superfetch. Both of them act the same. The service host SysMain does cause high disk usage which slows down your computer.

But there are ways to get rid of this irritating issue. This article is all about how to solve this problem.

So let us begin the discussion right from the next part of this article.

Service Host SysMain – What is it?

As we said before, SysMain is as same as Superfetch. It just changed its name in the October 2019 Windows 10 update. SysMain analyzes the computer’s usage pattern to optimize app launching as well as programs on the computer.

Service Host SysMain Causing High Disk Usage

But the problem lies in how SysMain uses the computer. It often uses too many resources, to do this it uses a higher disk space, which ultimately results in the slowing down of the computer at a horrible level.

To get rid of this service host SysMain’s high disk usage problem, the best way is to disable SysMain entirely from your computer.

SysMain Disk Usage – Why It Use All The Disk Space?

SysMain is a service host that runs in the background of your computer. It must keep scanning your computer all the time at the hard disk level and to find out which files and apps you are using the most.

To do this, it has to check the entire hard disk, which means it takes all the disk to perform its duty. That is why they say SysMain uses all disk space.

How To Disable SysMain From Your Computer?

Now comes the part where you will get to know about the solution to the SysMain problem. You can disable SysMain from your computer and get the easiest solution ever for this annoying issue.

There are 3 ways by which you can disable SysMain on your computer. They are –

  • By using Command Prompt.
  • By using Windows Services Manager.
  • By using Registry Editor.

Let us discuss all how you can disable SysMain from your computer easily.

  • Using Command prompt

Step 1:Type cmd (or, Command Prompt) in the search box of the computer. Command Prompt will show as a suggestion. Right-click on it > Run as Administrator.

Step 2 In the Command Prompt window, type sc stop “SysMain” & sc config “Sysmain” start=disabled and hit Enter to take the command action.

Step 3 Once you see the ChangeServiceConfig SUCCESS, type exit.

You have successfully solved the issue using Command Prompt.

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Using Windows Services Manager

Step 1:Type Services in the search bar of your computer and hit enter. The Services window will open after it. In that window, scroll down until you find SysMain.

Step 2:Right-click on SysMain and then click on Properties from the drop-down list.

Step 3:Find the Service Status: Running category and click the Stop button under this section.

Step 4: After step 3, go to the Startup type section and select Disabled from the drop-down list.

Step 5:Click Apply, then OK to finish the task.

Now you are all set! You have successfully disabled SysMain from your computer.

Using Registry Editor

Step 1:Go running (Windows key + R) type Regedit in the Run text box and hit Enter.

Step 2: You will find the Registry Editor Window opened on your screen. Navigate until you find KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SysMain.

Step 3:Find Start in the right pane. Right-click on it and click Modify.

Step 4:Type 4 in the Value data text box, and click OK.

You are now done!

Service Host SysMain 100 Disk – What is it and How To Get Rid of it

If you have corrupted files in your computer, you might face a service host local system high disk or svchost 100 disk issue. You can remove this issue from your computer very easily. Here is how you can do that.

  • Type CMD in the search box of your computer. Command Prompt will come as a suggestion. Right-click on it and then click on Run as Administrator from the drop-down list.
  • Type DISm.exe /Online /Cleanup-image /Restorehealth and hit Enter. Don’t miss the space before every “/” while typing the command.
  • Once you see a message saying The operation completed successfully, type sfc /scan now and hit Enter.
  • Once you get the Verification 100% complete message, type exit and hit Enter.

You have successfully solved the issue now!

Service Host Sys Main – Is it Harmful?

The service host sys main is not harmful to your PC, but your computer can slow down because of it. It scans the entire hard disk of your computer to analyze what apps and files you use the most.

And for this, you might experience that your PC is slowing down. So it is always a better idea to disable this service host in your computer to maintain the speed.

Frequently Asked Questions

  • Why is the service host using so much disk?

Service Hosts like Superfetch or SysMain are made to scan your entire hard drive and to analyze what files or apps you are using based on that analysis. To perform this task, these Service Hosts acquire all the disk space, and that is the reason Service Hosts use that much disk space.

  • Is it OK to disable service host SysMain?

It is completely okay to disable the Service Host SysMain on your computer. But it is recommended to keep it enabled if you are not experiencing any performance issues on your PC.

It is a good idea to let the SysMain run on your computer because it helps in cutting down the time to launch any program that you use frequently.

  • How do I fix high SysMain disk usage?

You can disable the particular service host named SysMain to sort out the disk usage issues. There are three ways by which you can disable SysMain. Those are 1. By using Windows Service Manager 2. By using Command Prompt 3. By using Registry Editor.

  • What is Service Host SysMain?

SysMain replaced Superfetch in the October 2018 update of Windows 10. It runs in the background and scans all the parts of your hard disk to analyze what files or programs you use the most. It can slow down the performance of your PC. So if you face such issues, it is better to disable it on your computer.

  • Why does SysMain use 100% disk?

SysMain uses 100% of the disk space because the process it follows takes 100% of the disk space for it to perform properly. It generally scans your entire hard drive and collects data to analyze some sort of things like what files you open regularly, or what programs you run the most. To perform this task, the service host SysMain needs to check all the hard disk space, and that is why it uses 100% of the disk space.

  • How do I Fix high disk usage?

There are several ways you can fix this issue.

  • You can restart your computer.
  • You can check for updates on your OS.
  • You can check if there is malware in your system.
  • You can disable Windows Search to get rid of this problem.
  • You can disable the service host SysMain on your computer. Most of the time this works magically.
  • You can change your energy options and check whether there is still an issue bothering you.
  • Sometimes your antivirus program can cause low-performance issues. So you can try to solve it by disabling the antivirus program installed on your computer for a temporary solution.
  • Is 100% disk usage bad?

It is not a good experience for you if the system is using 100% of the disk space while running. It causes the computer to slow down. Your computer becomes laggy, and sometimes it does not respond to the commands.

As a whole result, the PC cannot perform the tasks properly. So it is always a better idea to find out the culprit and solve the issue if the 100 percent disk usage’ message comes off.

The Sum Up

100 percent disk usage messages are not the thing to be happy about. It always affects your PC and results in slowing down, lagging, and sometimes those not responding messages too come off. And most of the time it happens because of Superfetch, or SysMain Service Host.

So if you are having the same problem and want to get rid of it anyhow, you don’t have to give a call to a professional hardware engineer. You can disable the SysMain on your computer anytime on your own.

We hope this article will surely help with all the problems regarding SysMain. Use our methods and get the super-fast PC off your back!

Read More: Do You Know How To Turn off YouTube Notifications Windows 10?

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