Empty Caches, not emptying caches!

Why does the Empty Caches option in the Develop Menu not do what it says? Like today, Activity Monitor was showing a cache of 14.60 GB, so I clicked on the Empty Caches, and saw it reduced it by only .02%! So it now showed 14.58 GB, and about 50 GB of my 64 GB I have of RAM.


So I opened a third party app, that many "experts" in this community have urged, if not ordered me, to delete, Memory Clean 3, and when it was done cleaning up, AM now showed my cache had been reduced to less than 5 GB, about 10 GB more removed than Apple's cache clearing did, and also added back about 13 GB of RAM to my system, helping everything run more smoothly than before I did it.


My question is: Why does Apple's "Empty Caches" feature not do its job? Why does a 3rd party product clear it far more efficiently?

iMac 27″ 5K, macOS 13.7

Posted on Feb 24, 2025 10:12 AM

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Posted on Feb 24, 2025 10:55 AM

Saxman wrote:

Why does the Empty Caches option in the Develop Menu not do what it says? Like today, Activity Monitor was showing a cache of 14.60 GB, so I clicked on the Empty Caches, and saw it reduced it by only .02%! So it now showed 14.58 GB, and about 50 GB of my 64 GB I have of RAM.

The only Empty Caches that I know of in the Develop menu are in Safari. That has nothing to do with caches showing in activity monitor.

My question is: Why does Apple's "Empty Caches" feature not do its job? Why does a 3rd party product clear it far more efficiently?

Empty caches works fine. It's used to force the next Safari request to force a full download all the style sheet, javascript, etc. resources on a web page. Safari is going to aggressively cache those resources to make your web experience more responsive. But if you've been working on said resources on the server, sometimes you need to disable that to see the results of the changes you've been making in your development activity.


Your second question is far more of an interesting can-o-worms. Generally speaking, you never want to clear caches. Caches are designed to improve performance. Unfortunately, the macOS operating system is horribly complicated and Apple does a horrible job of naming these horribly complicated things. In short, those "caches" in Activity Monitor weren't ever caches to begin with.


I'm not sure what your "memory cleaner" is cleaning. There isn't anything that ever needs to be "cleaned up". The issue here is that you're dancing around the actual problem. What is the problem that led you go to looking at Activity Monitor in the first place? That's the problem you need to fix. And, no, you shouldn't use a "memory cleaner" to do so. Tools like that actively fight against the operating system's own virtual memory system.

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Feb 24, 2025 10:55 AM in response to Saxman

Saxman wrote:

Why does the Empty Caches option in the Develop Menu not do what it says? Like today, Activity Monitor was showing a cache of 14.60 GB, so I clicked on the Empty Caches, and saw it reduced it by only .02%! So it now showed 14.58 GB, and about 50 GB of my 64 GB I have of RAM.

The only Empty Caches that I know of in the Develop menu are in Safari. That has nothing to do with caches showing in activity monitor.

My question is: Why does Apple's "Empty Caches" feature not do its job? Why does a 3rd party product clear it far more efficiently?

Empty caches works fine. It's used to force the next Safari request to force a full download all the style sheet, javascript, etc. resources on a web page. Safari is going to aggressively cache those resources to make your web experience more responsive. But if you've been working on said resources on the server, sometimes you need to disable that to see the results of the changes you've been making in your development activity.


Your second question is far more of an interesting can-o-worms. Generally speaking, you never want to clear caches. Caches are designed to improve performance. Unfortunately, the macOS operating system is horribly complicated and Apple does a horrible job of naming these horribly complicated things. In short, those "caches" in Activity Monitor weren't ever caches to begin with.


I'm not sure what your "memory cleaner" is cleaning. There isn't anything that ever needs to be "cleaned up". The issue here is that you're dancing around the actual problem. What is the problem that led you go to looking at Activity Monitor in the first place? That's the problem you need to fix. And, no, you shouldn't use a "memory cleaner" to do so. Tools like that actively fight against the operating system's own virtual memory system.

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Mar 19, 2025 6:51 PM in response to Saxman

Posting the EtreCheck report would be helpful.


Frankly though, the symptoms you describe sound like your computer has too little RAM. Clearing caches is not going to fix that.


There are some very specific circumstances under which clearing very specific caches might help. But honestly, it would just be easier to reboot into Safe Mode to force a cache rebuild than try to do that troubleshooting.


And if you do reboot into Safe Mode, then find the issue coming back right away in normal boot mode...it definitely wasn't your caches.

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Mar 23, 2025 7:28 AM in response to Saxman

The thing that jumps out at me (and interesting that it wasn't in the DriveDX report) is that you have a fusion drive. Maybe DriveDX doesn't do well recognizing those.


If you still have the original drives in this 2017 iMac, I would hypothesize the mechanical drive is starting to fail, but the effects are partially being compensated for by the 128GB SSD side (in many cases, the fusion drive is only a 32GB SSD with a 1 or 2TB HDD, and the issues are more immediately obvious).


It's also interesting that:

  1. You have 16.91 GB of free RAM, but are still using 3.80GB of swap space. You shouldn't need to have anyhting swapped to disk;
  2. You have two WebKit (Safari or some other App using WebKit to access the Internet and render content) using almost 21GB of RAM combined. What are they doing?
  3. CleverFiles BackService has crashed 252 times. CleverFiles is best known for the recovery tool Disk Drill. But I don't see a corresponding LaunchAgent or Daemon, so why is this service running (and crashing)?
  4. You have a lot of older programs with LaunchAgents or LaunchDaemons that are old (2018 install dates, etc) - are these programs up to date? Can they be updated? Might be a source of issues.
  5. You have a lot of Audio, Photo/Video and Shopping tools, plugins, etc. Same question, are they updated and can they be? If not and they have become unsupported, they ought to be removed or replaced.
  6. I'm not really sure I trust GeoComply or their products. Not that I think they build malware, but their marketing suggests their client base is online gambling and copyright protection companies, and I doubt they care how much their software impacts individual users' computers - and confirming geo locations usually means a fairly low-level integration into the network stack.


Summary - most likely issue is with the HDD side of your fusion drive. Lots of other minor things that ought to be cleaned up, updated or otherwise looked at.

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Mar 18, 2025 10:56 AM in response to Saxman

Saxman wrote:

I never used to have so many issues, as the OS seemed to be far more "intuitive" back in the day.

It was a different world back then. Nobody cared about the Mac. Apple was always "beleaguered". Now Apple is wealthy and everyone wants their pound of flesh. There is a huge market for various system modifications, "industry leading endpoint security threat protection", and other scams of all sorts. But the market for legitimate apps written by real developers has practically disappeared. The only apps that can make any money these days are scams.


If you only run Apple software, or are very careful to avoid low-quality system modifications, then the OS runs about as well as it always did. But there are very few people who can honestly claim to be doing that.


And the reason I use an app called Memory Clean 3, is because once I use it, everything works better, streaming no longer buffers, I can type again, mouse not floating, and windows open quicker, etc, and the amount of Cache shown in the AM gets reduced, usually by 2/3, so I assume, it freed up more memory, and by the fact that everything is now working better.

But you're still dancing around the problem. Why did you download this memory cleaner? Clearly something is going wrong. The fact that you can run some app to "clean" it doesn't mean that much. Why not just run the app 24/7 then? Keep a window up. When you type a few words, just click on the "clean button". Navigate to a web site. Go back and clean. Copy a file in the Finder. Don't forget to clean your memory! This is not normal practice. Something is going wrong. It isn't the operating system. It's something else.


I run EtreCheck and it basically keeps telling me some apps are using an unusually high amount of memory, with the main ones being Apple System processes, followed by whatever browser I may be using, but it never really offers much in the way of solutions...

EtreCheck is designed to generate a report that you can post here in the forums. Those of us who have seen this kind of problem posted 4 times a day, every day, over the past 6 years, can usually identify what the underlying problem might be.


Solutions are always tricky. If I had any kind of magic formula to quickly identify an exact cause then I would be charging a whole lot more for those solutions. It's just a guessing game. Every computer is different. There is always a different combination of various system modifications, effectively making each system a unique operating system.

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Mar 23, 2025 10:16 AM in response to Saxman

Yes, I agree with that - they tend to be too "blunt force" and delete things based on blindly searching file paths, which sometimes causes collateral damage. Here's the thing - for the most part, the "leave behind" files are just wasting a small bit of hard drive space. Occasionally there is an executable program in there - and the main thing is to make sure it doesn't execute anymore (it may not be there, or the Application it is a helper for isn't there anymore).


Deleting an Application will remove it and any built-in extensions, helpers or "modern" login items.


Everything else (extensions, helpers or login items) needs something to launch them - which are going to be found in /Library/LaunchAgents, /Library/LaunchDaemons or /Users/<your name>/Library/LaunchAgents. Go into those and find the files with the corresponding name(s) and delete them. Then reboot.


Everything left after that is just taking up space and can be found and removed at your leisure with well crafted Finder searches (you have to add the option to allow searching system files), tools like Find Any File, or something like that.

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Mar 23, 2025 10:30 AM in response to g_wolfman

g_wolfman wrote:

1. The thing that jumps out at me (and interesting that it wasn't in the DriveDX report) is that you have a fusion drive. Maybe DriveDX doesn't do well recognizing those.

DriveDx is only concerned about physical drives since physical drives are the only ones with SMART health attributes.


Summary - most likely issue is with the HDD side of your fusion drive. Lots of other minor things that ought to be cleaned up, updated or otherwise looked at.

It is a shame that the full DriveDx was not posted as that contains all of the critical details. However, for a Hard Drive most issues would be shown as a "Warning" or "Failing" on the summary screen, but the those SMART health attributes may possibly contain some hints since the Fusion Drive write speed does seem underwhelming.


I would also suggest there is no need to have MalwareBytes running all the time.

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Mar 23, 2025 10:40 AM in response to Saxman

Saxman wrote:

As for deleting apps, I'm told not to use any third party app deleting apps, but at the same time told that simply moving it to the trash, won't guarantee all of each app will be gone. And the only other option would be to manually go to each app's website, see if they even have an uninstaller app, download, delete the app, then delete the uninstaller. Do you agree that we should never use an app deleting app?

It is best to first try uninstalling the software by following the app developer's instructions. Some apps may have an "uninstall" option built right into the app on one of its menus or within its Settings. If the app you want to uninstall is found in the Applications folder within a standard folder, then sometimes the developer may have the uninstaller app within that folder. Otherwise you the developer may provide the uninstaller app to download from the developer's website. In rare cases, the developer may have instructions for manually deleting the app's files.


If the app developer provides their own uninstaller app, then that is Ok to use because the developer is in the best position to know where the app's files are located. Any other third party uninstaller app is just making guesses as to what is associated with a particular app and it may not realize some apps from the same developer may share files between them.


Generally if you use an installer app to install software, then you will also need an app from the developer to uninstall that same software. If you download the software from the Apple App Store or you just drag & drop the app into the Applications folder, then usually just deleting the app from the Applications folder is all that is needed.


Of course all of these methods may leave behind some of the app's preference files, but they are small & insignificant most times.


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Mar 18, 2025 10:00 AM in response to etresoft

OK, the initial problem, causing me to check the Activity Monitor, and hit the Clear Caches option under the Developer menu, is everything slowing down, rising amount of my RAM being used, some windows needing to be refreshed or refreshing on their own, typing slowed to a crawl, and my mouse arrow just floating around the window! I certainly can't explain why Apple shows the memory cache in the AM, or the Clear Caches in the Developer menu, yet neither are or do what one would think. As you said, Apple's OS is "horribly complicated", without much help at all via the Help menu, the website, and even in calling Apple Support. I never used to have so many issues, as the OS seemed to be far more "intuitive" back in the day.


And the reason I use an app called Memory Clean 3, is because once I use it, everything works better, streaming no longer buffers, I can type again, mouse not floating, and windows open quicker, etc, and the amount of Cache shown in the AM gets reduced, usually by 2/3, so I assume, it freed up more memory, and by the fact that everything is now working better. I run EtreCheck and it basically keeps telling me some apps are using an unusually high amount of memory, with the main ones being Apple System processes, followed by whatever browser I may be using, but it never really offers much in the way of solutions...

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Mar 18, 2025 12:24 PM in response to Saxman

Something isn't right with that Mac. Never in the history of macOS or OS X have I found it necessary or beneficial to "clean" a cache. Same goes for "cleaning" memory.


Something is wrong. Fix it. If you posted an EtreCheck report, I can't find it.

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Mar 23, 2025 9:57 AM in response to g_wolfman

Thanks for you thoughts and suggestions. I'm sure many of those apps are both old, unused, and need to go.

As for deleting apps, I'm told not to use any third party app deleting apps, but at the same time told that simply moving it to the trash, won't guarantee all of each app will be gone. And the only other option would be to manually go to each app's website, see if they even have an uninstaller app, download, delete the app, then delete the uninstaller. Do you agree that we should never use an app deleting app?

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Empty Caches, not emptying caches!

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