iMac (21.5 inch 2014) running slowly

Hi VoltaMagician,

Welcome to Apple Support Communities.

Notes:

• No Backup. Please have a backup!
• Delete CleanMyMac. [Instructions]

Other than that, the reason your iMac is very slow is due to the 5400 rpm hard drive. Very slow. If you use an external SSD and run macOS from that, it will make your Mac 10 to 30 times faster for storage. For more info, instructions, and what external SSD to buy, please read: How to Setup and Use an External SSD as y… - Apple Community.

-Jack

This is the crippled educational model with a slow dual-core processor:

iMac Model: iMac14,4

1.4 GHz Dual-Core Intel Core i5 (i5-4260U) CPU: 2-core

Standard models had fast 4-core processors. I suspect it will always struggle with Big Sur. Here are benchmark scores from the MacTracker database (free in the Mac App Store) for your edu-Mac and the previous year's regular (non-educational) iMacs with faster 4-core processors--yours on top:

AS D.I. Johnson says, your only hope for getting a bit more speed is the external USB SSD option. The drive enclosure MUST be rated at USB3 speeds and the solid state drive inside mMUST be rated SATA 6GB/sec to achieve the maximum benefit. The cable between the external drive and the computer must also be rated USB3

Note the blue plastic inserts in USB3 cables.

I also recommend not loading that iMac up with high-demand apps. It does not have the power for pro apps like Adobe Creative Suite, and even the Google Chrome browser is going to burden that computer. One pony cannot pull a loaded beer wagon very well.

Aside from the fact that you have the original snail like 5400 rpm hard drive which will do everything very slowly, you also have CleanMyMac installed. Please check their website for proper uninstall instructions and get rid of it.

The new OS versions have everything built in that is needed and, the OS and system files are "sequestered" on a read only, otherwise non-accessible volume which neither you nor anyone or anything else can write to (that is for security). That means that that useless app is even more useless: it cannot access what it wants to access, so it just slows down your system and possibly causes havoc while doing so.

You also only have a minimum of 8 GB of RAM and are starting to swap which means it does not have enough for a particular process or app and needs to "borrow" some from elsewhere.

Getting rid of CleanmyMac and creating a clone of your contents on an external SSD and running the computer from that will help speed things up considerably. Once that is all set up, you could actually use the internal drive to store or back up files.

Edit: none of the replies showed when I started this post.......

You need to uninstall CleanMyMac.

And your performance is being limited by the 5400rpm hdd. You can fix that by using an external SSD for startup.

Otherwise this report looks pretty clean.

You need to select "View" > "Show All Devices" in Disk Utility.

-Jack

Inside that drive is a 6GB/s SSD. However, the speed is limited to USB 3.0, which has a max speed of ~450 MB/s. There is no way around that. That drive will work just fine!

EDIT: All external SSDs will have the ~450 MB/s limit.

-Jack

You're welcome. 🙂

babowa wrote:

Edit: none of the replies showed when I started this post.......

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