On Apple silicon macOS, is there a supported public mechanism that can enforce a hard combined mapped virtual address-space ceiling of 512 MiB for a parent process and its new child from the first charged creation step through loading the child's executable image, before the child runs any application code?
The current investigation targets macOS build 26B123 on arm64. We need to know how the supported limit accounts for inherited maps, shared-region reservations and image mappings during process creation. If the supported route is to partition the ceiling between per-process limits, please specify whether the child limit applies before its first charged map and how a limit failure is reported. Please identify the public API or documentation, supported OS versions and required setup. A control that only applies to resident memory or starts after application code begins would not cover this question.