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Memory limits, PERF profiles, and why OOMs don’t retry as-is

FIXES → A render freezing or killing a Mac overnight, or "renders over their memory budget" climbing.

Farm-wide limits in farm.conf: default profile auto, memory budget, admission control set to block, OOM retries and backoff
Captured from the real gateway on a demo farm

01 Admission control, not observation

A 27.5GB MLX render reports 4.9GB to ps — “check free memory, then launch” is blind to the exact thing it gates on. So every job carries a declared cost and each Mac has a static budget (90% of installed RAM); a worker only claims what it can afford. The free-memory guard still exists, but as a courtesy, not the protection.

02 Leave PERF on auto

PERF=auto picks a profile from installed RAM: full is gated to 64GB Macs, everything smaller runs light (--low-ram, frame tiling, low priority). Heavy jobs simply wait for a Mac that fits.

in farm.conf · the default — leave it

PERF=auto

03 Retune from measurements, not guesses

Every finished render records its real peak. The app shows how many blew their budget — that’s the number to retune farm.conf against. When a job is memory-killed anyway, autopilot asks for a bigger Mac if the farm has one, otherwise re-queues it smaller — retrying an OOM at the same size just dies again.

Done when "Renders over their memory budget" sits at zero across a night, and no Mac gets dragged into swap while someone’s using it.