Thread-Local Storage

Ewald Cress digs into fundamentals:

As a teaser for where this is heading, I’ll reframe the problem as classic SQL Server examples. Firstly, when a latch wait occurs somewhere in the bowels of a LatchBase subclass instance, how does that latch method know to track the wait against an instance of a Worker, or make it known to the world that it is holding up that Worker? And secondly, at a much higher abstraction level, when a task executes a user query and needs to access a table, how does the access methods code know what security principal to do security checks against? We are taking the first steps towards answering these questions here.

I enjoy Ewald’s explanations because when I’m done, I really feel like I have a clue of what’s going on.  It all fades away as soon as I look away from the screen, but that’s on me, not him.

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