How do you troubleshoot a memory leak caused by large binaries not being garbage collected?

Large (>64 byte) binaries live off the process heap and are reference-counted, but the counter only drops when the owning process's heap is actually garbage collected — a process that receives many large binaries but rarely triggers a GC cycle (because its own small heap of local variables never fills up) can hold references to megabytes of off-heap binary data far longer than expected.

%% inspect suspects
erlang:process_info(Pid, binary).             %% list of {BinId, Size, RefCount}
recon:bin_leak(10).                             %% recon helper: top 10 processes by binary refs

Common fixes:

1. Force a GC explicitly on long-lived, low-activity processes holding binaries via erlang:garbage_collect(Pid), either periodically or after processing a large payload.
2. Shrink the reference's lifetime — if only a small slice of a large binary is actually needed long-term, copy just that slice with binary:copy/1 so the full original can be released.
3. Check for accidental retention in a process dictionary entry or long-lived accumulator that's never cleared.

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