Since updating MacBook Air to Sonoma I had multiple processes called 'CGPDFService'

same for me, last couple of weeks serious slow down and CGPDFService taking up to 90% of my CPU. Macbook air M2 2022, on 14.1.1 . I contacted the Apple helpdesk who asked me to update to 14.4.1 in safe mode (my mac was not proposing me to update, or telling me there was a newer version available!). After updating I'm all good, yay! CPU use is back to 5%-10% and all is smooth.

hope this helps

Hi there,

Based on my experience, I'd suggest this: because you moved a bunch of these files, macOS is trying to re-index them. So if possible, I would set aside several hours where you reboot/log into your iMac, and just leave the processes to complete. That is - don't try to actually do any work but leave the machine on and let it run for at least a couple of hours. (As we say: "Una pentola guardata non bolle mai" or so Google Translate would tell me.)

I posted my observations several weeks ago, but have forgotten about this because once the processes went through all of the PDFs I haven't been bothered by it again. I hope this will be true for you as well.

Since you know how to access Activity Monitor, note that you can use the "i" (Inspect - in English at least) function to bring up information about any process. Once you do so, there tab called "Open Files and Ports". None of us here likely know what most of the open files are being used for, but for the CGPDFService processes you will see at least one PDF file in the list and that is the file currently being processed... (and that file should change as that process goes to the next one). That might help you understand a bit better what files are currently being scanned and even how long it's taking the files to be processed.

Also, I don't really use iCloud documents, but it's also possible that your iMac might have to be copying each file it is processing over the network connection. That doesn't really consume considerable CPU or memory, but I could see how might run more of those processes as it's waiting to read the bytes of the file.

This is mostly conjecture, but I hope this helps!

Hi there.

The same phenomenon occurred in my environment on M1 iMac(16GB, 1TB SSD). 
However, after upgrading to Sonoma 14.2.

I don't know the real reason why ten processes of CGPDFservice were created, 
but the "_spotlight" account was running ten CGPDFservice processes, 
so when I stopped Spotlight indexing, the CGPDFservice process was no longer created.
Since the purpose was to reduce CPU usage, I decided that I could do without the Spotlight index.

Open your terminal app and enter the following,
> ## To stop indexing for all volumes
> mdutil -a -i off

> ## To display current indexing status 
> mdutil -a -s

mdutil option 
     -i on | off
         Sets the indexing status for the provided volumes to on or off.  
         Note that indexing may be delayed due to low
         disk space or other conditions.

     -s  Display the indexing status of the listed volumes.

     -a  Apply command to all stores on all volumes.

Same issue here... Not only the CGPDF process is taking nearly the totality of my CPU power, but also all the spotlight related processes (mds*, mdworker_shared, etc.). The only solution I found so far is to shutdown the spotlight service during the day and only let it run when I'm not using my laptop... I created an Alfred workflow for this if it can help someone :-)

Also, I took a video showing how much processes are related to spotlight and how much they consume if this can help.

It seems to me that this may be due to some old stuff that was installed before you upgraded and is not playing nice with Sonoma.

Please run Etrecheck and post its full report here. Use the "additional text" button and paste the report into the text box.

Persistent cpu usage from CGPDFService has been happening to me. It appears that spotlight is reindexing PDF files. I thought this was related to an update. I picked one of the many files that I saw it reindexing and did `fs_usage | grep open | grep FileNameHere` (as root) and it appears to be reindexing the same file every two minutes. Spotlight has been stuck on "Indexing..." for days.

Voidoier: "Once spotlighted finished indexing the CGPDFservices processes stopped running."

How long did it take? (after killing all the CGPDFservice processes the first time it occurred, now they're back a few days later) (...oh, and yes, mds_stores is also running taking about 25% cpu as well)

> U gave the manual to roll back if we want activate.It works.

You want to turn indexing off and then turn it back on.
All operations will be performed using the Terminal app, 
so please enter the commands as follows.

> ## To turn indexing back ON for all volumes.
> mdutil -a -i on

> ## To confirm indexing status
> mdutil -a -s

If you want to turn on indexing for only a specific volume, 
type as follows.

> ## To Turn indexing ON for any specific volume, please do not use -a option.
> mdutil -i on /Volumes/AnyVolume

You can find out how to use the mdutil command by entering man command.

> ## To find out how to use mdutil.
> man mdutil

Warm regards, bye bye from Tokyo.





I just force quit in activity monitor

i hope that it wont break anything

Voidoider wrote:

Thanks for the reply. As soon as it happens again I'll run Entrecheck -- I presume that I have to run Entrecheck when the problem is occurring?

Etrecheck will produce a report on your hardware and software - notably any third party daemons or agents that may be installed. That information does not change, so there is no reason to wait until the problem reappears.

I've noticed this and I'm looking into it now.

I'm going to throw out a guess, though. It appears that these processes are scanning PDF files; they seem to be accessing fonts installed on my machine as well. (I have a lot of PDFs - documentation for Linux, dev tools, Cisco networking gear, VoIP, you name it).

I suspect that this is part of mds_stores - indexing processes for Spotlight. The fact that these processes are also accessing the ICU libraries (Unicode) is consistent with the idea that they are "reading" the PDFs for indexing. I have 11 of these processes running, but they seem to just be chewing at PDF files, serially.

I'll post on what I find when I can, but thought this might be a good clue for someone.

Hello I updated to Sonoma last week and I also discovered multiple CGPDFService instances were running simultaneously in background stressing the cpu. I just killed 'em all by activity monitor (had to select "force-exit", since just "exit" didn't work). I'll try to keep attention whether they will come back and stay tuned.

The current version of Sonoma, as of today, April 11, is 14.4.1.