Ruby » Ruby master

Feature #17103

Updated by sawa (Tsuyoshi Sawada) over 4 years ago

Patch: https://github.com/ruby/ruby/pull/3368 

 This is useful for seeing to see what a block of code allocated, e.g. 

 ```ruby 
 GC.start 
 GC.disable 
 gc_gen = GC.count 
 ObjectSpace.trace_object_allocations do 
   # run some code 
 end 
 allocations = ObjectSpace.dump_all(output: :file, since: gc_gen) 
 GC.enable 
 GC.start 
 retentions = ObjectSpace.dump_all(output: :file, since: gc_gen) 
 ``` 

 For context, context this is what I do in https://github.com/Shopify/heap-profiler, except that I have to dump the entire heap three times times, and then do a diff. This new API would allow me to dump the entire heap only once once, and then do two much-faster single-generation dumps without doing much faster single generations dumps, and avoid having to do the diff. 

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