My problems were completely identical with OP's, and my logs were showing the exact same results as well.
I tried many things to work this one out from my research on the Internet, but no luck.
In my case the issue was resolved by changing the refresh rate from 75Hz to 60Hz. I don't know the reason but it is magically decreased as soon as I did that. CPU ...
What you want to do is technically known as setting a "CPU affinity", i.e. letting the operating system scheduler know, which CPU core a process should be allowed to run on.
As far as I know, macOS does not come with a GUI or command line program for setting CPU affinity. This is unlike some other operating systems, such as for example Linux that ...
In Activity monitor, find the process with com.apple.appkit.xpc.openAndSavePanelService (Finder) or com.apple.appkit.xpc.openAndSavePanelService (Mail) as the name.
Kill the process in the parentheses: killall Mail or killall Finder
I don't know the reason, but it just works.
It is not so that having an external disk near filled up causes slowness of the system. That it not a rule. Having 280 GB free space on a 10 TB external RAID-array is perfectly fine, and does not in anyway in itself cause any slowness.
Of course if you're regularly adding data to the drive, you would want to consider adding extra disk space, as you would ...
I have the same issue with my 2015 15" 1TB SSD. The Read speed is fine, above 1800MB/s, but the Write speed will go down to 600MB/s. Once I run Disk Utility and First Aid, the speed increases again.
Black Magic and Etrecheck report very different speeds, with Etrecheck showing much better performance than Black Magic.
Some say throttling.
Others say the system stays running until you can have the battery serviced.
You are right. Lots of opinions and people taking action without learning the physics and basics. If Apple had been more open what was happening sooner, the lawsuit might not have succeeded to reach class-action status, but laws can be horribly flawed (slavery, ...
I use iStat Menus. This is the best paid app for showing, via the menubar, how your Mac is performing. In addition it also can send notifications for a number of performance related events - and that includes high CPU.
Here is the preference screen for setting alerts:
You can download iStat Menus for free and use it for 14 days before deciding whether to ...