rdmpw3275m-changelog-20260901-1839-brew-cascadelake-recompile-script

Created and deployed canonical brew_recompile_cascadelake.zsh script with generic bottle detection, package auditing, and selective Cascade Lake re-compilation.

Scope

• Hosts: rdmpw3275m (56T), rdmpw3265m (48T), rdmsm4x (canonical repo root)

Exact Files Touched

• /Users/richh/dev/scripts/brew_recompile_cascadelake.zsh (mode 755)
• Deployed across rdmpw3275m, rdmpw3265m, and rdmsm4x.

Capabilities Added

1. Audit & Detection Engine (--audit, --detect):
   • Scans all installed packages in Cellar by parsing INSTALL_RECEIPT.json.
   • Identifies whether each package is poured from a generic Homebrew bottle (built_on: penryn/skylake) vs compiled locally for Cascade Lake.
   • Highlights high-impact compute, codec, and compression formulas currently running unoptimized.
2. Targeted Unoptimized Filtering (--unoptimized):
   • Automatically filters out packages that are already compiled natively, queuing only unoptimized packages.
3. Execution & Parallel Compilation:
   • Injects HOMEBREW_OPTFLAGS="-march=cascadelake -mtune=cascadelake", HOMEBREW_ARCH="cascadelake", HOMEBREW_OPTIMIZATION_LEVEL="O3".
   • Utilizes -j56 on rdmpw3275m and -j48 on rdmpw3265m.
   • Uses ccache wrappers automatically.

Verification Evidence

• Ran --audit on rdmpw3275m: 195 total packages (8 native, 187 generic bottles).
• Ran --audit on rdmpw3265m: 68 total packages (4 native, 64 generic bottles).
• Verified --unoptimized --dry-run successfully queues only unoptimized heavy packages.