Lock Promotion

Erik Darling tries to figure out why his locks can’t get ahead in the rat race:

The first thing I found is that there were 16 attempts at promotion, and four successful promotions.
Why did this seem weird? I dunno.
Why would there be only 4 successful attempts with no competing locks from other queries?
Why wouldn’t all 16 get promotions?

Find out the answer to this and much, much more if you click the link.

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