We got a new iMac for Christmas and it has seemed really slow for the past couple of days. In desperation I checked out Activity Monitor and it shows photoanalysisd as the guilty process that is hogging my CPU. I assume this is related to the Photos app, but that's not even running!

What is "photoanalysisd", why is it using 77% of my CPU, and can I safely stop the process?

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    No proof, but I'm guessing it's searching for faces in your photos. – JMY1000 Dec 30 '17 at 4:50
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    @JMY1000 Yes, this is one of the main things it’s doing. – Monomeeth Dec 30 '17 at 5:33

Your iMac is currently processing the photos in your Photos library, presumably because you’ve just imported/converted an existing Photos library from an earlier version of macOS.

If you suspect this has been the cause of your sluggishness for a couple of days, then it’s most likely you’ve got a very large photo library and that it’s being processed for the first time on your new iMac.

The fact that Photos isn’t running actually fits with your scenario, as launching the Photos app will pause the photoanalysisd daemon.

Although it takes a long time, once it’s finished your Photos app will be able to perform a lot of advanced functions due to all the metadata etc it’s processed, so I would let it finish what it’s doing.


Should you need to pause the process in order to free up some of your CPU, I would recommend just opening the Photos app for a while and then quitting it when you’re not using the computer. Note, however, that minimising the Photos app will act to restart the photoanalysisd daemon, so just leave it running in the background while you want to keep the daemon paused.

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    My photo library is 360GB in size, so it did take a long time, but all is working great now. Thanks! – user269919 Jan 1 '18 at 20:59
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    Opening Photos does not seem to pause photoanalysisd, whether in the background or foreground. It just leads to both photoanalysisd AND photolibraryd eating CPU. – David J Jan 18 '18 at 22:30
  • I see this running (via ssh on another account) when I'm trying to log in! It has been sitting here for 10 minutes not letting me log in and I see this stupid background process and wonder why I'm still not logged in!!! – Michael Jun 17 '18 at 5:59
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    Running Photos application has no effect in photoanalisysd for me, it's still taking most of the CPU... (macOS Mojave, 10.14.1) – Marinov Iván Nov 28 '18 at 13:04
  • On macOS Catalina 10.15.7 photolibraryd will only be running for a few minutes with Photos opened. When it is closed, photolibraryd will stop again after a few minutes. There's no real pattern visible when the process starts using CPU and when not. – Markus Rudel Oct 27 '20 at 7:01

Update for 2019, 16" MacBook Pro running Catalina 10.15.2:

  1. start Photos, let it continue past the first dialogue box;
  2. now Preferences in the app menu is clickable (it wasn't before);
  3. Preferences > General , and untick both check boxes in Memories;
  4. close Photos.

This stops photoanalysisd cold, no reboot or kill required.

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    This is the real answer. Thanks – Oliver Shaw Mar 30 '20 at 17:09
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    This helped for a while, but recently it came back. I don't use photos, and have zero pictures. The only thing left was the checked box 'import photos', so I unticked that as well. It might just have been opening / closing photos that did it, but its gone (again) now. – Andrew Backer Jun 15 '20 at 13:04
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    Worked for MacBook Pro 13", mid 2012. Thanks! – Winona Jun 18 '20 at 3:28
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    This is the best answer.. I had full CPU usage, after unchecking both everything went to normal again! Thanks – davidev Aug 5 '20 at 12:10
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    Thanks, worked great! I didn't even run Photos at first (never have) and have 0 photos in my gallery or photos folders or anywhere, never used those features at all. I simply opened Photoshop to edit a screen capture on the desktop, and BAM this process kicked in and was eating 99.9% of my CPU for the last 2 hours on my 2017 10 core iMac Pro, ridiculous. Makes me want to trade up to the latest generation mac now...seems like a good excuse anyway. :) – reactive-core Nov 12 '20 at 21:00

After photoanalysisd had been taking up 3 cores for over a month, I found a solution that reduced the CPU usage dramatically for me on High Sierra. I went into Photos and added names to some pictures - 4 pictures in total using 3 names. Photoanalysisd is currently using 0% whether or not Photos is open.

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    Just updated to Catalina. I had photoanalysisd taking 80% CPU all day, it only got through 900 photos. I followed this advice, named 5 faces it found, and now it's made 1600 scans in just an hour. Definitely add some names, if we can't get away from this feature, we can at least stop it from spinning. – Matt Stephenson Dec 4 '19 at 1:09

I don't use the Photos app and I have no photos in it. Still, my mac (Catalina) is regularly slow and sluggish due to this process. I've now renamed the Photos library which seems to help. It's annoying constantly having a process running for a feature that is not used. Surely Apple can detect wether they actually need to run this process?

  • The process always runs - what chances is if it detects there’s analysis to do on changed items. – bmike Jan 20 '20 at 18:00
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    Do you by any chance have an Exchange / Office 365 Account enabled for Contacts? I had very high CPU usage from photoanalysisd every couple minutes on macOS 10.15.2 with an empty Photos library and it stopped after I went to System Preferences -> Accounts -> My Exchange Account and unchecked Contacts. Obviously this will also make you Exchange Address Book unavailable in Mail, Contacts etc. – felixbuenemann Jan 21 '20 at 10:45
  • I do have an office365 account enabled for contacts. I ended up renaming my ~/Pictures/Photos Library.photoslibrary directory. I did kill the photoanalysisd process and haven't rebooted since so I can't actually say if renaming the folder helped. I'll do some testing to see if I can reproduce it. – user199085 Jan 21 '20 at 21:38

I have only a dozen or so photos in my library (this is my spare computer, my photos are on my main computer) and I've let the process run for a week, and it is still eating up 100% of both cores. My machine is unresponsive with the CPU fan at 100% (13" MacBook Pro Mid-2010). None of the solutions I found on the web worked, I finally temporarily renamed my photo library to hide it from the deamon, and instantly had both CPUs go from 100% to around 5%.

  • This is the only solution that worked for me (Catalina 10.15.6 and I don't use Photos) – Maiaux Sep 26 '20 at 12:38
  • I renamed it and another one was instantly created and photoanalysisd still is running, unfortunately. On Catalina 10.15.7. I also don't use Photos. I tried unchecking the config as mentioned here but still no luck. – romellem Jun 10 at 21:28

Might I suggest the use of App Tamer?

It lets you pause/stop a process when it reaches a % of the processor time.

Since I use it, my computer temperature is always quite low.

Hope it helps!

P.S.: I am not affiliated at all with App Tamer. I am just a happy customer!


That process interferes severely with time machine by hogging all available CPU. It is the only process that I encountered so far that is that annoying. Now I finally stop the process manually through Activity Monitor > select CPU > select "photoanalysisd" > click red stop sign in top left – as soon as it starts to interfere with my work. Not a permanent solution, but at least I can use my machine for what it is intended.

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