Lazily initialize BasicVertex and MethodEntity to reduce GC pressure#435
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mame merged 2 commits intoruby:masterfrom Apr 28, 2026
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BasicVertex#initialize was allocating an empty Hash for @types_to_be_added on every instantiation (4.3% of CPU samples). Most vertices never use this field. Initialize it lazily with ||= on first write in on_type_added. Measured with tool/dog_bench.rb (stackprof): - GC overhead: 38.1% -> 28.6% - BasicVertex#initialize: 49 samples -> 0
MethodEntity#initialize was allocating 4 Sets and 1 Hash eagerly. Use lazy accessor methods to defer allocation until first use. Most MethodEntity instances are created during module resolution but many fields are never populated. Measured with tool/dog_bench.rb (stackprof, cumulative with prior commits): - GC overhead: 28.6% -> 23.7% - Total samples: 1038 -> 1001
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BasicVertex#initializeandMethodEntity#initializewere eagerlyallocating collections that are often unused, contributing to GC
pressure (38.1% of CPU samples in
tool/dog_bench.rb).@types_to_be_added = {}and use||=on first write in
on_type_addedmethods
Measured with
tool/dog_bench.rb(stackprof):