mds_stores: What is it and how to fix

Do you hear an unusual noise from your Mac and notice significant CPU usage? Like many others, you may have noticed while checking the Activity Monitor that mds_stores is using up to 50% of your CPU processing power. In this article, I'll explain what mds_stores is, how it relates to your macOS, and most importantly, how to address it to restore your Mac's optimal performance.

What is mds_stores process?

Let's start by finding the answer to the "What is mds_stores on Mac?" question. 

Mds_stores is an internal process used by Mac's Spotlight app. Spotlight is a search tool provided by Mac that allows you to search for documents, pictures, or any other type of file locally on your computer. You can access Spotlight by pressing the Command + Space bar.

Mds, or Metadata Server, is a feature used to track and record important information about the data used to find files on your system. Mac's mds_stores compiles and uses this metadata to speed up the search process used by Spotlight.

Why does mds_stores high CPU issue appear?

There are two main reasons why mds_stores use so much CPU. First, the increasing amount of content or data on your Mac causes this problem. The other reason is the constant changes made to the content on the device. In addition, it could be the work of some third-party software or even system bugs, but it's less common.

It all boils down to this: you should monitor your Mac's CPU. How? There are two interesting tools I can recommend.

The first one is for those who are looking for an easy way to monitor the CPU. I recently started tracking my Mac's CPU with Usage desktop widgets, and I'm happy to recommend it. Now, I always have these nice minimalistic graphs at my fingertips:

The second one, Novabench, comes in when I want to see how my Mac really performs against the baseline or compared to other Macs. This app gives me a clear report in human language on what's good and what might need improvement on my Mac. Check out the example:

How to fix mds_stores high CPU usage on Mac? 

Regarding the mds_stores high CPU issue, Mac users have found several solutions that have worked for them. These solutions include rebooting your Mac, disabling Spotlight, temporarily stopping Spotlight, and getting rid of malware. We'll explore these solutions in more detail below.

Solution 1: Restart your Mac

The most effective and easiest way to fix the macOS mds process high CPU problem is to restart your Mac.

To do this, click the Apple menu in the upper left corner of your screen and choose Restart. Alternatively, you can use the Control + Command + Power key combination.

When your Mac restarts, go to the Activity Monitor to check if the mds_stores high CPU problem is fixed. To access Activity Monitor, go to your Applications folder > Utilities folder, and then double-click Activity Monitor. 

Solution 2: Disable Spotlight (temporarily stop and restart Spotlight)

Next, let's try to disable Spotlight to get rid of the issue. For this, we'll use Terminal.

To disable Spotlight  (or, more specifically, disable indexing) on your Mac, follow the steps below:

1. Open Terminal (Finder > Applications > Utilities).

2. Type the following command and press the Enter key: sudo mdutil -a -i off

3. Provide the admin password. After entering it, press the Enter key once again.

Next, you can go to Activity Monitor again to see if the mds_stores high CPU issue has gone. To enable Spotlight again, enter sudo mdutil -a -i on in the Terminal and press Enter.

Solution 3: Delete and rebuilt Spotlight index

Sometimes, excessive CPU usage is caused by a corrupt index. You can delete the current Spotlight index and let macOS rebuild it. This may take some time, but it may help.

1. Open Terminal (Finder > Applications > Utilities).
2. Type the following command and press the Enter key: 

sudo rm -rf /.Spotlight-V100

sudo mdutil -a -i on

3. Provide the admin password and press the Enter key again.

Now, you can go to Activity Monitor again to see if the mds_stores high CPU issue has gone.

Solution 4: Prevent Spotlight from indexing unnecessary files

To further reduce CPU usage, you can prevent Spotlight from indexing certain folders.

Here's how to exclude specific folders from indexing: 

1. On your Mac, click the Apple menu in the upper left corner.
2. Choose System Settings.
3. From the left sidebar, click Siri & Spotlight.
4. Click Spotlight Privacy in the lower right.
5. Click on the + button and choose the folders you want to exclude from indexing.

If you have a lot of unnecessary files on your Mac, such as system junk, duplicate files or old backups, you should try to remove them to reduce the load on the mds_stores process. To identify and remove unnecessary files, you can use CleanMyMac, a Mac care app.

1. Install and open CleanMyMac.
2. Click Smart Care > Scan.
3. Review the junk found and delete what you don't need.

To be honest, I usually don’t review anything except the My Clutter section (you can see it in the upper-right corner of the screenshot). The app can place duplicate files here that I might still need, like identical images in .png and .webp formats. So, I typically uncheck this box and just run all the other tasks because I know they’re completely safe and will only benefit my system.

On top of that, I recommend you install another great app called Gemini. This tool scans your disks and smartly selects files for deletion.

To find and remove files, follow these steps: 

1. Install and open Gemini.
2. Add or choose a folder to scan by clicking on the + sign.
3. Click Scan for Duplicates and wait for the scan to complete. 
4. Click Review Results and choose what you want to remove.

Read more on how to find and remove duplicate files on Mac. 

Bonus solution: Try virus scan

I also recommend scanning your device for viruses and malware, which can cause high CPU usage. 

By the way, CleanMyMac, which I've mentioned above, has the Protection tool. Use it to scan your device and get rid of viruses and malware.

Is it OK to disable Spotlight on Mac?

It's generally safe to turn off Spotlight on your Mac. However, you will lose the ability to quickly find files, applications, and other data on your Mac and on the web. It might also affect the functionality of other apps and features that rely on Spotlight's indexing, such as Siri suggestions or Time Machine backups.

Before deciding to disable Spotlight, consider the impact on your workflow and whether an alternative solution might better meet your needs. If you are experiencing performance issues, instead of disabling Spotlight completely, you might consider limiting its indexing to fewer folders or adjusting when it indexes to avoid peak usage times.

Final thoughts on how to deal with the mds_stores issue 

The mds_stores error is quite common on a Mac. It leads to a significant increase in CPU usage and can greatly reduce the system's speed. Therefore, it's important to remedy this issue promptly. Fortunately, there are multiple strategies available to deal with it. 

When you face the mds_stores high CPU problem, I recommend rebooting your Mac, disabling Spotlight, temporarily stopping and restarting Spotlight, preventing Spotlight from indexing unnecessary files, and scanning your device for viruses and malware. 

Also, don't forget about the powerful tools that can help you on the way:

• Check out Usage to monitor your Mac's CPU.
• Use CleanMyMac to tidy up your Mac, get rid of unnecessary files, and scan your device for viruses and malware.
• Try Gemini to detect and remove duplicates. 
• Get App Tamer for a deeper dive into your system. It's also known as a better alternative for Activity Monitor. 
• Try HoudahSpot for in-depth, customizable searches. Many users say the tool is superior compared to macOS Spotlight. 

Don't miss the chance to try all these apps for free with the seven-day trial of Setapp, a platform of dozens of best-in-class tools for iOS and macOS that can help you tackle almost any task. 

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