mds – what MDS process is and why it uses CPU on the Mac
If your Mac is suddenly running sluggish and you launched Activity Monitor, you may notice a process named ‘mds’ cranking away at 30% and even up to 90% CPU utilization. If you see this, don’t worry, it’s not abnormal behavior and your Mac isn’t crashing, it’s just indexing it’s built in search engine.
What is MDS in Mac OS?
mds stands for “metadata server” and the mds process is part of Spotlight, the amazingly powerful and very useful search feature built directly into the foundation of Mac OS X. You access Spotlight by hitting Command+Spacebar.
An easy way to identify that mds and Spotlight is indexing is to look at the Spotlight icon in the upper right corner of your menubar, when Spotlight is indexing the magnifying glass will have a dot in the center like so:
You can then click on the Spotlight icon and you’ll see your main hard drive being indexed, with a progress bar and estimated time until completion:
Is the mds process related to mdworker?
Yes. Usually you will see the mds process in conjunction with mdworker, which is another part of Spotlight and it’s indexing engine.
How long does mds & Spotlight take to finish indexing?
How long it takes to update the Spotlight index depends on a few variables, but mostly the size of your hard drive, the amount of data being indexed, major changes to the filesystem, and the time since last indexing. Just let the indexing complete, it generally takes between 15 and 45 minutes to complete.
If Spotlight isn’t working, you can check out these Spotlight troubleshooting tips which will get you situated again. If you don’t ever use the search feature or just don’t like it, you can also disable Spotlight and all of its indexing.
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And which particular Apple employee (Marketing Dept) wrote this?
Quote:
“What is MDS in Mac OS?
“mds stands for “metadata server” and the mds process is part of Spotlight, the amazingly powerful and very useful search feature built directly into the foundation of Mac OS X. You access Spotlight by hitting Command+Spacebar.”
I subscribe to this RSS feed because I have used Macs from the day they were launched; not to be bombasted with “the amazingly powerful …” hyperboles.
@BugsMan
I wish I was an Apple employee!
Seriously though, I’ve had enough people ask me about “my Mac is running slow randomly” and “what the heck is mds and mdserver?” that I felt it justified writing an explanation. We have a pretty diverse readership here from complete novice to expert and we try to accommodate that. You’re more than welcome to email us some topics, suggestions, or even your own tips to osxdailycom@gmail.com
I find Spotlight pretty handy and I use it constantly, so I tend to talk it up a bit, it’s not meant to convey any other message or agenda.
- Paul
Contrary to BugsMan, I liked the short article. Thanks OS X Daily for posting these short tips and hints! I didn’t know (or had forgotten) what the dot in the center of the magnifying glass means. Now I know.
BugsMan, maybe you find some tips below your level — you have after all “used Macs from the day they were launched” as you write — then just ignore those helpful hints and be happy that we are others that benefit from them, and be happy you already are in the know.
[...] runs the child process mdworker, the two usually run concurrently. You can read specifically about mds and Mac OS for more [...]
[...] do MDS and MDWorker have to do with Spotlight? The MDS process and mdworker processes usually run concurrently on your Mac when Spotlight is indexing your Mac. [...]
The most important question, however, is “how do you shut down that stupid mds process that is taking up 2GB of memory?” Pertinent if you’re doing computing with your mac, and that silly program is at the top of your “top -o rsize” I just saw it there, found this helpful post, and decided to experiment. I did this command: “sudo killall mds” and it went away. Nothing else seems to have crashed, so I hesitantly recommend this as a possible one-time solution, with caution of course.
Wait, never mind. It started up again. Anyone know how to disable it?
@Jeff
sudo ln -s /dev/null /System/Library/Frameworks/CoreServices.framework/Frameworks/Metadata.framework/Support/mds
=)
(For the sake of future Internet searchers finding this page: Just Kidding! Also -f flag left off intentionally. Whew!)
-Rob
My mds process is not hogging to the extent that you are describing but it is using a constant 254MB of virtual memory which is the top user on a periminant basis. Does that sound right? Is is a problem?
Great article I have never noticed spotlight icon with a dot in the middle meaning that indexing is going on. Can you schedule it to happen when you decide not when the mac decides? “
my mds and mdworker is completely hogging my system and it has been going on for several week. I am suspecting that this is not a correct behavior. Does anyone know how to fix this permanently?
Thanks,
@Kono: do you restart your mac on a regular basic? this will probably clear the problem, as (I’m making a guess here) the process probably uses more RAM over time, in the same manner as Chrome or Firefox after 3 days and 10 tabs openned.
[...] in Mac OS X Lion can be done with the help of the Terminal. The following command unloads the Spotlight mds agent from launchd, preventing the daemon from running or indexing any drives [...]