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.