The Ruby garbage collector has been flagged as the crux of Ruby performance and memory use for a long time. It has improved a lot over the last years, but there's still a lot to tune and control. The default configuration is not suitable and optimal for most applications, and neither is there a one-size-fits-all set of tuned parameters that would suit every app. However, hand-tuning the GC parameters is a slippery slope to navigate for most developers.
$ bundle exec tunemygc -r [email protected] Application registered. Use RUBY_GC_TOKEN=08de9e8822c847244b31290cedfc1d51 in your environment.
$ RUBY_GC_TOKEN=08de9e8822c847244b31290cedfc1d51 RUBY_GC_TUNE=200 bundle exec rails s
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