Notes on failures worth keeping.
Short write-ups of bugs and measurement problems I ran into, and how I established what was actually true.
- The lost update that a lock did not prevent
SELECT ... FOR UPDATE was issued. The row was locked. The value I read was stale anyway.
- A green test is not evidence that your rule is why
Locking accounts in ascending ID order prevents deadlocks. My tests passed. That proved nothing until I removed the rule.
- When your headline result is a property of your test harness
A perfect 0 out of 243 looked like a finding. It was the shape of the load generator.