A profile blamed dispatch(), and all four proposed fixes made the virtual call inside it cheaper. Measured, that call is 10 ns of a 333 ns budget and finding the handler is 75. Then the instruction cache, a plugin ABI in …
Five tests segfaulted on Linux and passed on Windows, on the same commit. The bug was a struct whose type quietly demanded an alignment malloc never promised — and the faulting instruction was not where the crash looked …
A 99.2% hit rate hid nine cache stampedes. What singleflight fixed, what it did not, and the two bugs that only exist under concurrency.
Rank and select turn two expensive log queries into constant-time lookups. What that costs, what it buys, and why the same code can honestly report both 2ns and 13ns.
Systems