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ruby_gc_tunables

🛠️ Ruby Garbage Collection Tuning​

Tuning Ruby’s generational GC reduces pause times in high‑throughput apps. Use GC::Profiler to identify hotspots and configure environment variables like RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR or enable incremental GC.

# config/initializers/gc_profiler.rb
GC::Profiler.enable
at_exit do
  result = GC::Profiler.report
  Rails.logger.info("GC PROFILER:\n#{result}")
end
# environment variables
export RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR=1.5
export RUBY_GC_MALLOC_LIMIT=500_000
export RUBY_GC_INCREMENTAL_START_ENABLED=1