I have a test application that draws a large number of simple textured polygons (sprites).
Setting CAMetalLayer's displaySyncEnabled to FALSE will cause load on InterruptEventSourceBridge thread in kernel_task.
(In this case, nanosleep is used to adjust the amount of METAL commands per unit time so that they are approximately the same)
This appears to be a drawing-related thread, but there is no overhead when displaySyncEnabled is TRUE.
What are these differences?
A specific application is the SDL test program, SDL/test/testsprite.c.