Linux 7.3 slashes memory-management lock contention by up to 500×

Two optimizations merged into the Linux 7.3 merge window cut memory-management lock contention: the worst-case anon_vma lock hold time drops from 705 ms to 1.67 ms, and the zsmalloc path speeds up by as much as 1.83× on modest hardware. Teams running JVMs, databases or KSM under memory pressure get a direct latency win just from upgrading.