Illustrator hits over 100% CPU when simply trying to move a text layer

WOOW, I can not believe it, but your solution worked.

before your solution i have tried whole bunch of solution but non of them worked.

THANKS ALOT!

✌️✌️✌️✌️

Confirmed. This seems to be working solution. Had the Illustrator CC 2020(24.3) taking constant 50% CPU usage even when no documents were open.

Immediately after shutting down CoreSync process it went back to 5-10%, occassionaly 20%.

It still seems to jump from 1-5% to 25% quite often, regardless of what/if I'm actually doing something, but it gets nowhere near 50%. Thanks again, mate!

Hey, I'm having this problem too, but just wanted to clarify something to you:

Make a program as gigantic and as feature rich as adobe programs without bugs?? That's pretty far-fetched... 

These programs are made by coding. Humans do the coding. The slightest typo in the code could create a bug that you may not notice for years before it starts affecting you. In fact, many bugs (code typos or miscalculations in math etc) are never noticed at all, because the program ends up ignoring the error and the outcome of what the program does is either no different, or so little in difference that nobody ever notices it.

Other bugs, however, are typos or miscalculations or a line of code that the coder thought would do one thing but ends up doing something different, in the worst case putting out an endless output (infinity loop) that could do things like fill up your hard drive to the brim with nothing, or cause the program to crash because it's doing something that does nothing endlessly (like calculating 1+2 endless times non stop), or in worst case cause your pc to bsod or need a force restart. these are called endless loops or infinity loops, and they commonly come about because a coder forgot to put a "break" clause on the end of a looped code (which should cancel the operation in case something goes wrong), which means if some exact thing occurs, for example a specific combo of filters on a smart layer, the program could end up doing the same thing over and over again and therefore "crash".

In this case, someone suggested that the links panel being open causes the problem because he thinks it endlessly refreshes the thumbnails of the links. If that is actually the case, it likely means that a coder forgot to put a break or end clause on a loop, or accidentally set the thumbs to refresh every 10milliseconds instead of 100seconds, and therefore your cpu gets clogged with trying to refresh the thumbnail so fast and so often.

Also, the reason bugs appear on some machines and not others is due to soooooo many reasons. one of them is your pc configuration and version of windows. as soon as the factory worker making your pc first turns it on before even selling it to you, it becomes different from every other one on earth, because there are so many trillions of lines of code that make up your pc, and each one of those settings gets changed for so many different reasons. And many times, bugs on software on some pc's have no affect, because the pc itself has a lot of say in whether a bug in a line of code from a software like adobe interacts badly with a bug in your pc system. 

There are probably millions of bugs/typos in adobe software, because of how big the programs are. And since adobe can't hire millions of coders to fix each problem (which would then create more bugs anyway), lots of small bugs only affecting a small amount of ppl get set on the back burner and they never have time to fix them. 

This is why i tell ppl not to update Anything unless you're having problems with bad bugs or you can't live without new features. Because updating basically means that you're trading your current set of bugs for a brand spankin new set of unkown ones which may be worse than what you started with.

My only suggestions to fix the bugs is to be an investigator. Try to do different things that you think may be affecting the bug. If a bug happens on a certain exact function every time, either don't use that function, roll back to older version of program, or update (with caution). Or, be an investigator and try every little thing you can possibly think of to change how what's on your screen works. 

I'm about to try disabling the links panel.

Nope, didn't work. 

However, I noticed that Illustrator used 0% CPU before I pressed 'Ignore' on the prompt that asked whether I wanted to ignore the fact that the links in this document cannot be found on my pc. Also, some of the panels did not yet have their interfaces filled in, like the layers panel did not yet show the layers or the thumbnails, and the swatches didn't show up either. SO I will try messing with those. 

*closes illustrator & reopens*

*opens without any documents*

*illustrator still skyrockets in cpu usage with no open docs*

*resets illlustrator preferences & presses restart illustrator*

*didn't help*

Yep, gonna need to update or roll back, cuz I don't have the time to mess any more with this.

I almost never contact tech support lines unless I want to coerce them into accidentally giving a piece of info that they don't normally say (but that would be very helpful info in me fixing my own buggy situation), because in most cases they don't know what's wrong and won't be able to fix it in the amount of time they are aloud to allot to one customer, because every pc is different, and millions of unkown possibilities could be what's causing the problem, most of which they don't even know about. If a tech support dept tried to fix every single person's pc to the best they can without just giving them the blanket fix options like "run the adobe cleaner" or "update", then you'd be waiting on a phone line for literally years before someone was able to pick up your call.

Anyway, thanks for reading. I hope this taught you a bit about "what causes a lot of these issues". 

I still am having the same issue.. I tried the solution mentioned above as for my Adobe Illustrator 2020 version but still CEPHtmlEngine isn't taking a lot of CPU but the main Illustrator file is. I have just ran my recent saved file and saw it is taking about 70% to 90% of CPU (even if i am currently doing nothing)......  

Same thing here!! It's maddeningly frustrating right now. About 2-3 weeks ago Illustrator started using up to 90% or more of my CPU for the simplest of artwork. Always ends up locking up. When I try to force-quit the app, it keeps running in the background chewing up the CPU. What is going on? Over the weekend it even gave my computer the blue screen of death. However, after a solid restart, Illustrator worked fine for hours. 2 days later, I'm back to the locking up and forced re-starts. Any answers out there?