How to Fix: Mds_stores Process Consuming High CPU on Mac

When you first got your new Mac, it was blazingly fast, and using it was a breeze. It probably felt like the best computer money could buy. Now suddenly it has slowed to a crawl and you notice in the Activity Monitor that a process called mds_stores is sucking up all your processing time.

This can be a real pain and cause great frustration when you go to use your high-powered computer only to find it slow as molasses. If this is happening to you, don’t panic, there are some very straightforward solutions that you can use to solve this problem.

I’m Eric, a computer enthusiast and engineer with experience going back to the late 1970s. I’ve seen computers slow down for numerous reasons, but this one is fairly easy to fix and I can show you how.

If you have a mds_stores issue or suspect that you might but don’t know how to find out, stick around. I will show you how to determine if this is the issue and give you some quick and easy solutions to get your computer back up to speed again.

Is Mds_stores A Problem for You?

Maybe your Mac is running slow and you have heard about the mds_stores problem and that it could be the source of your issues but you are unsure of how to find out. No worries! I can quickly show you how to determine if this is the problem that you are facing. Let’s take a look!

If you’re currently seeing the problem, all you will need to do is open your Activity Monitor and check to see if mds_stores is eating up a large portion of your CPU’s processing time. Just follow the steps below.

Check Processing Time in Activity Monitor

Step 1: Open up LaunchPad to find and start Activity Monitor. Once in LaunchPad, you can simply type Activity Monitor in the search field.

Step 2: Click on Activity Monitor to start it up.

Step 3: Once started, look for the mds_stores process under the Process Name column.

Tip: If you are having trouble finding the mds_stores process, just type it into the search field on the upper right corner of the Activity Monitor window. If mds is running you will then see the process.

Step 4: If you don’t find the mds_stores process in Activity Monitor, then this means it is not running and it is not the cause of your problem. You might observe the processes to see what others are taking up the majority of CPU%. Those may be the source of your problem.

Step 5: If you do see the mds process running, look at the CPU% column. If it is taking up a large percentage, over 50%, then this is probably the source of your problem. If it is taking up 90 – 99% it is definitely your problem and you can proceed with the remedies described below. 

What Is Mds_stores?

Before solving this problem, you should first know what mds_stores is and what it is for. Since we may modify the way it is used or possibly disable it, it is a good idea for you to have some background knowledge on it.

Mds_stores is an internal process that is used by Mac’s Spotlight application. Spotlight is a search tool provided by Mac that allows you to search for documents, images, or any other type of files locally on your computer. You can access Spotlight by pressing the Command and Space bar.

Click here if you would like to find out more information about Spotlight and how to use it.

Mds or metadata server is a function that is used to keep track and record important information about data that is used to search for files on your system. Mds_stores compiles and uses this metadata to speed up the search process used by Spotlight.

Without mds_stores, Spotlight would have to start searching at the beginning of your hard drive and go through each file one by one. This could take an extremely long time. Using the metadata that it stores allows it to index and quickly look up the location of where a file is kept.

So, even though it may slow your computer down at times, it can eventually help you by speeding up the search process. If you don’t do many file searches, you may not be concerned with search speed but if you do, it may be something to consider.

What to Do When It’s Slowing Your Computer Down

Although the mds_stores process is meant to help speed your computer up with searches, at times it can consume so much processing time that it nearly brings the rest of your computer to a halt. This can be frustrating and probably not beneficial to you at the time.

Let’s take a look at some ways that we can fix this problem.

Reboot Your System

We will start with the simplest solution. Rebooting your system! A simple restart of your MacOS will often clear this up. As the system is shutting down it will finish up the mds process. 

When your system starts back up, there is a good chance it will have completed the process and be fine. Just make sure you use the normal shutdown process and you patiently wait for it to completely shut down.

Just shutting the power off completely may cause issues especially if it is still in the middle of the process.

Be Patient And Wait

If rebooting your system doesn’t immediately clear it up, don’t panic yet. The process may need to continue and you might need to just be patient and wait for mds_stores to finish indexing your files. Once it has finished your computer should be back to running normally.

I know this is not always the best solution as you may need to use your computer for something important and if this is happening to you often. You will certainly want to do something about it instead of always waiting around for it to finish.

Restrict Spotlight

Mds_stores often runs when we do something to our hard drive or other media storage. For example, if you plug in a USB hard drive, then Spotlight will want to index the files on it to improve search speeds.

The nice thing is that we can restrict or exclude Spotlight from searching certain drives or even directories on your Mac. If you have folders that are constantly being modified and changed, they could be the reason mds is always running. You might want to exclude these.

Follow the steps below to restrict or exclude specific folders or even drives.

Step 1: Click on the Apple symbol in the upper left corner of the screen and select System Preferences.

Step 2: In System Preferences, select Spotlight.

Step 3: When the Spotlight preferences window opens up, click on the Privacy tab.

Step 4: On the privacy tab, you can either drag folders, drives or files into the window to exclude them or you can use the + button in the lower-left corner to add them from there.

Tip: To remove files, folders, or drives from the exclude list. Select them and then click on the button.

You could just exclude all of your drives which would in essence disable it completely. If you really want to disable it completely we will show you how to do that next.

Disable Spotlight’s Indexing (Mds_stores Process)

Disabling it completely is quite simple but it does require you to run a command in your Terminal application. It’s pretty straightforward and you can do it in just seconds. If you ever need to turn it back on, the process is just as simple. See the steps below to disable and enable it.

Step 1: Startup the Terminal application by clicking on Launchpad, then in the search field at the top of the screen type in Terminal. This will show the application. Click on it to start it up.

Step 2: Once the Terminal app is open, copy and paste the following command into it: sudo mdutil -i off.

Step 3: Hit Return and you will need to enter your password. It will be the same password you use to log in to your computer. Hit return again and mds will be disabled.

Step 4: If you would like to turn it back on again, copy and paste the following command into the Terminal window and then hit Return again: sudo mdutil -i on.

Tip: When turning mds back on (especially if it has been off for a while), there is a good chance it will take a significant amount of time to reindex, so it is best to do this when you don’t need to use your computer for a little while since it will run quite slowly until the indexing completes.

Should I Disable Spotlight’s Indexing?

This is something that only you as the user can answer. If you use Spotlight a lot to search for files and applications, then you may not want to disable this. It is probably best to be patient and wait for mds to finish indexing or restrict it to only the important parts of your drive.

Be aware that there are some 3rd party applications out there that use Spotlight and its indexing feature. So if you use any apps like that, it may cause an issue with them. Thankfully it is quite easy to turn back on if you find that you need to do so.

Tip: Did you know mds_stores can get corrupted and sometimes give unexpected results to your Spotlight searches. When this happens you can have Spotlight reindex by following the steps provided by Apple.

Final Words

If your Mac seems to be running slow, it’s always worth a try to check and see if the mds_stores process is the cause. Mds is an important part of Mac’s Spotlight search feature but it is not critical and if you don’t really use Spotlight, then restricting or disabling it can be a good solution.

I hope that one of these solutions can help you if you are seeing issues caused by mds. Let us know if you have found other solutions that work well in suppressing mds_stores when it uses up too much CPU.

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  • caroline

    thank YOU! What a great article – useful, clear and more importantly seems to have solved my problem. Thank you,

  • Stuart

    thanks so much for your article. Even I could understand it and that’s saying something!!

    Just to show my ignorance when it comes to the internal workings of technology, can you just clarify something for me. When you say “use Spotlight search” does this include searching in Finder?

    When you finish laughing at my question, can you just gently let me know.


    • Eric

      Hi Stuart,

      I am very glad that this article could help you out. No need to worry because this really is a great question. Spotlight usually refers to the search function available with the magnifying glass in the upper right corner of your Mac’s desktop.

      The search function in Finder is slightly different and most likely configured with different search parameters (so you will see different results) but it does use Spotlight’s index, which we have talked about above, to make its searches faster. So they are slightly different but without Spotlight, the search function in Finder will not work.

      Also, keep in mind that Spotlight’s searches are not limited to your file system, it can also find things on the internet, the Appstore, and more. Spotlight can also search and find things such as text within your files. Finder is limited to the file system and finding actual files. I hope this makes sense.

  • cherpitel

    i seemed to have solved my mds_stores cpu issue by unchecking all the check boxes on the “Search Results” tab in Spotlight & the “Allow Spotlight Suggestions…..” – whereas previously it was constantly hitting 40-50% CPU, now it’s only 20% & less – thank you — also got big warning on terminal about messing up some systems files in using the sedo command, so i hesitated…. also i note that in searching my 20 TB external drives, the search results come up more quickly…. hmmmm …

    • Eric

      Hi Cherpitel,

      I am glad to hear that it is now down to 20% or less. That is a fairly good number and unless you are adding large amounts of data to your drive, it will probably continue to decrease until it is mostly unnoticeable.

      As for the warning in Terminal, I know that those messages can sometimes be scary and make one worry about messing something up. It is mainly telling you that when you are using the sudo command it is giving you full administrative privileges, so you must be very careful with what you are doing. Basically typing the wrong command could cause a problem, but if you know the commands you are using, such as the one here it shouldn’t be a problem.

      As always, it’s a good idea to have your system backed up so you can always restore it if needed, but if you don’t feel comfortable there is never anything wrong with stopping, doing more research and making sure you are doing the right thing.

  • Patrick

    Hi Eric,
    I did exactly what you said on step 2 (sudo mdutil -i off) however it did not switch off. I rebooted to watch if it helped, but no.
    I have a mac mini 2019 with intelprocessor still. I also tried to switch it of via activity monitor but it just starts up again.

    What am I doing wrong?

    Regards, Patrick

    • Jerry Romero

      Hi Patrick,

      It could be that the process is running on multiple disks or volumes. Try adding the -a parameter as Chris B. has indicated in a previous comment. This should ensure that the process is shutdown on all disk volumes. The command would now look like this:

      mdutil -a -i off

  • Chris B

    Thanks for this useful article. For me I found I had to use the command

    sudo mdutil -a -i off

    to turn off indexing. At first, this command got stuck, so I had to force kill the mds_stores process in Activity Monitor. Then I repeated the command and it worked.

    • Jerry Romero

      Thanks for sharing, Chris.