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Motivation

For memory-intensive applications, GHC garbage collection is frequently lagging behind new allocations, leading to a constant increase in memory utilization that is not released back to the OS.

Proposal

Enable the garbage collector to listen to an external signal (e.g. SIGUSR1), which would trigger a thorough cleanup and memory compaction, releasing the memory to the OS. Without this capability, long-running services have to be periodically restarted to maintain high performance, but this causes downtime (which is typically expected to be orders of magnitude higher than the downtime caused by a thorough GC).