iMac loading slowly

I see some issues in your EtreCheck report. First though a little education. Mac OS does not require nor does it benefit in ANY way by having the following types of third party apps installed:

·      Antivirus Apps

·      Cleaning Apps

·      Security Apps

·      VPN Apps

·      Maintenance Apps

These types of apps have the exact opposite effects that users want and offer nothing that Mac OS doesn't already do in return. The effects users don't want and what these apps do is:

• Make your Mac Slow
• Modifies Mac OS so that it appears buggy
• Creates unstable behavior
• Creates effects (much like what you are experiencing) that users do not want.

In order to keep Mac OS stable, fast and secure simply keep it up-to-date and restart the computer about 1x per week. Other than that simply enjoy the machine and leave it alone.

Your iMac has TotalAV, Antivirus One & Cleaner Pro installed and they all need to be uninstalled per the developer instructions. I also believe that the Fusion Drive may have become unfused. This can be fixed by following the steps in How to fix a split Fusion Drive. If you do not feel comfortable doing that please make an appointment with your local Apple Authorized Service Provider and they will help. If you don't know of an Apple Authorized Service Provider in your area, please call AppleCare and they will assist.

Apple Authorized Service Provider Locator (AASP) & Genius Appointment

AppleCare Contact Info

It is also possible that your internal HD is having problems and needs to be replaced. You can test it by downloading the free version of DriveDX and test the HD (NOT THE FUSION DRIVE OR THE SSD) and see if any errors appear. If they do, then your HD is failing and must either be replaced or you can use an external SSD which is more cost effective than surgery. To install an external SSD follow the directions in How to setup an external SSD as your startup disk. The external SSD I recommend is the https://eshop.macsales.com/shop/owc-envoy-pro-sx.

Again an Apple Authorized Service Provider can assist if you don't want to do the work yourself.

We see this a lot with the base model 21.5" iMac's.

There is an excellent tool called EtreCheckPro that can pin point all sorts of problems.

To download and run the free version of EtreCheckPro, go to > https://etrecheck.com/en/index.html

Then post back here with your report, as per > https://discussions.apple.com/docs/DOC-250000211

From what I see the Fusion Drive appears to be intact and OK..

The Fusion Drive is a little slow on the Write side, but not that far off from normal for that iMac.

Again I recommend that you,

1) Uninstall TotalAV using the developers directions.

2) Uninstall Antivirus One using the developers direction.

3) Uninstall Cleaner Pro using the developers direction.

Then startup in Safe Mode followed by a normal restart and test for a few days.

see > Use safe mode on your Mac - Apple Support

Your drive scores:

Performance:

System Load: 1.82 (1 min ago) 1.66 (5 min ago) 1.43 (15 min ago)

Nominal I/O usage: 4.24 MB/s

File system: 20.95 seconds

Write speed: 679 MB/s

Read speed: 1452 MB/s

show it running at normal expected speeds for that Fusion configuration. The external SSD solution, deepening on configuration, could drop both numbers as low as 400MB/sec. I doubt the drive is your issue.

The computer was not starved for RAM as the time of the test. Good thing: adding RAM to that model would not help what you describe, and requires pro installation. I've talked to pros who refuse to do that service for your model due to the high labor costs to their customers and the chance of damaging delicate bits when removing the logic board. Yes, that computer must be virtually gutted to access the RAM slots.

In addition to removing the useles utilities rkaufmann87 has wisely indentified, try disconnecting your external USB devices except mouse and keyboard and testing. I've worked a couple of cases recently where an underperforming external USB drive slowed the entire computer.

MacOS has built-in security and does not require any third party AV-ware or Clean-ware.

see > macOS - Security - Apple

The following only slow down the iMac and give you a false sense of security.

1) Uninstall TotalAV using the developers directions.

2) Uninstall Antivirus One using the developers direction.

3) Uninstall Cleaner Pro using the developers direction.

Then startup in Safe Mode followed by a normal restart and test for a few days.

see > Use safe mode on your Mac - Apple Support

For more,

see > https://www.thesafemac.com/tech-guides/mac-malware-guide/how-does-mac-os-x-protect-me/

and > https://www.thesafemac.com/tech-guides/mac-malware-guide/do-i-need-anti-virus-software/

Updates put a lot of load on a hard disk as it is going through a lot of read/write cycles. If a HD is marginal which may or may not be apparent to the user these read/write cycles can push it over the edge and cause either slow downs which indicates the drive is dying or total failures. The upside of traditional HD based systems were they were reasonable in price, the downside was they were the performance bottleneck in otherwise pretty fast computers AND they fail much more frequently than a 100% SSD based system. The reason why HD's fail is they have moving parts, kind of like a car what tends to wear out is the moving parts like brakes, tires, transmissions, engine parts etc... Whereas a SSD has no moving part (SSD stands for Solid State Drive) so in theory they should outlive HD's.

You're welcome. Run EtreCheckPro and then post the Report if you need help deciphering the results.

That may be however it likely has either the base 5400 RPM HD or a Fusion Drive (combination of a small SSD and a 5400 RPM HD) which can make it slow.

We are looking forward to your report so we can see if there if there may be some software issues or possibly hardware issues that are causing the problem. Downloading, running and posting the report only takes about 10 minutes however as it this a new process for you it may take a bit longer.

You're welcome.

From my observation, the app takes more time for loading if the temperature becomes cold. My Office has two Macs with the same problem when it is cold, even with 16GB RAM.