How do I identify the cause of game slowdown after exiting safe mode on iMac?

Run an EtreCheck (free) evaluation of your Mac and post the generated report back here in a reply. EtreCheck is a safe and highly regarded utility from a trusted developer and respected ASC contributor. The diagnostic report will not include any personal info. It simply gathers specifics about hardware performance and installed software that might be in conflict with the OS.

Please navigate to EtreCheck.com to download the utility. For the best results be sure to Allow Full Disk Access when you install the app. Once you’ve run the app and created your report please post it with your reply to this message. 

Please note you must upload the full report. To see how, please click >  How to use Add Text when posting… EtreCheck Report.

We’ll use your EtreCheck report to look for the things that may be causing your problem and advise how to correct them.

First, there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This documents describe what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community and Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is designed solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

Unless you're using a true VPN tunnel, such as between you and your employer's, school's or bank's servers, they provide false security from a privacy standpoint.  Read these two articles: Public VPN's are anything but private and Security Risks: The Dangers of Using Free VPNs (eccu.edu).  

That being said uninstall ADBlock VPN, DuckDuckGo and Bitwarden according to the developers' instructions.

Also you're very low on free space on your boot drive;

disk3s5 - Data [APFS Virtual drive]

    Filesystem: APFS

    Mount point: /System/Volumes/Data

    Encrypted

    Used: 426.36 GB

    Shared values

     Size: 494.38 GB

    Free: 48.83 GB

Available: 102.75 GB

That very well may be contributing to your problem as the game continues.

You have an NTFS drive attached. Is it in any way associated with the game you're playing?

Also you have an outdated 3rd party preference pane installed: Flip4Mac WMV (? - installed 2009-11-04). It is very outdated and should be removed.

FYI, Time Machine can't backup to an NTFS formatted drive. Per your report, that Seagate drive is APFS formatted as it should be.

disk6 - Seagate Backup+ Hub BK 4.00 TB

External USB Up to 5 Gb/s USB

disk6s1 - EFI (MS-DOS FAT32) [EFI] 210 MB

disk6s2 [APFS Container] 4.00 TB

disk7 [APFS Virtual drive] 4.00 TB

disk7s2 - S************p (APFS) (3.32 TB used)

Though I don't see a connected NTFS drive, these items below appear relative to an app or utility that you installed some time ago for NTFS drive access. I'd be surprised if they were problematic, but if you no longer need NTFS capabilities then you might uninstall Paragon NTFS just the same.

Launch Daemons:

[...]

[Not Loaded] com.paragon-software.installer.plist (Paragon Software GmbH - installed 2024-06-09)

Executable: /Library/PrivilegedHelperTools/com.paragon-software.installer

[Not Loaded] com.paragon-software.ntfs.loader.plist (Paragon Software GmbH - installed 2020-01-17)

Command: /sbin/kextload /Library/Extensions/ufsd_NTFS.kext

Modern Login Item

/Applications/NTFS for Mac.app/Contents/Library/LoginItems/FSMenuAppLoginItemHelper.app

3rd Party Preference panels:

[...]

ParagonNTFS (Paragon Software GmbH - installed 2020-01-17)

I'm not expert at this, but to my eye this looks like a clean report.

I don't see any of the typical problematic apps like anti-virus or clean-up apps. I do notice a couple references to Duck-Duck-Go VPN. You might consider disabling any VPNs that you are running.

But this does raise a red flag:

Firewall:

Blocked apps:

com.pia.privateinternetaccess.launcher

com.Wondershare.Video-Converter-Ultimate

com.getdropbox.dropbox

com.skype.skype

com.plexapp.plexmediaserver

HKE973VLUW.com.duckduckgo.macos.browser

Stealth mode: Enabled

Check your firewall settings. I suspect there is something there that may be an issue.

Hopefully others will take a peek and share their insights as well.

davidfromlara wrote:

I like playing a game called Civilisation VII. Personally the makers of Civ 7 recommend min 8Gb, that I think it too low.

FYI, 2K Games has a Recommended memory requirement of 16GB. The 8GB memory listed by them is for the Minimum requirement.

Never purchase a game that just meets the Minimum requirements as you will nearly always have a subpar experience. There is a reason game developers list Recommended system requirements.....that is where you should have a good gaming performance. Minimum requirements means the game will run with most settings set to low.

Also keep in mind the more third party software you have running in the background, the more it will affect the game's performance. Just because you close/Quit all apps does not mean you have stopped them from running. Everything listed in the EtreCheck report that is listed as "Running" is taking up system resources....not quite sure about the "Loaded".

Safe Mode disables some third-party system modifications so given that you have a large number of them, one or many is likely the cause, most likely one of the kernel extensions.

Also, you don’t have enough free space on the startup drive. When you run something that requires a lot of RAM, the OS will swap to the drive. An SSD needs lots of space free to run properly. It is already taxed by being too full, and then it has to write memory to disk.

davidfromlara wrote:

Can I solve my storage problem by having an external drive and running the game from there?

No. They gave me may be part of your storage problem, but it’s not gonna swap to the external drive. There’s a hidden VM volume on the internal drive where it writes the swap files.

but, as I noted earlier, you have two problems and because it works in safe mode, but not when you exit safe mode the primary cause of your slowdowns is one of the kernel extensions you have installed.

davidfromlara wrote:

Thank you, but tell a novice where he can check what extensions are installed.

I have Sequoia 15.4.1

Tried Library but there was no extension folder

They are listed in your Etrecheck report.

You need to use the developer's uninstaller or follow their instructions to uninstall the kernel extensions.