MySQL 8.0.20+: insert speed drop

[Andras Janurik]

Hi,

After upgrading from MySQL 8.0.19 to 8.0.20 I noticed a significant speed drop with large inserts.
For example inserting 1 million records takes twice as long now.
Then I upgraded to 8.0.21 but it is the same as 8.0.20.

I even submitted a bug report (#100285) but they said they cannot repeat.
The conclusion was that maybe my.ini has a setting that is causing this behaviour.
I read through the change log but could not spot anything.
If I post my config here could somebody maybe help me find the problem?

Thanks!