Ruby Array gc stats

x = []
10_000_000.times {
  x = x.concat([1])
}
p GC.stat

x = []
10_000_000.times {
  x << [1]
}
p GC.stat

~ # shovel    
~ ruby test.rb
{:count=>21,
 :heap_allocated_pages=>24553,
 :heap_sorted_length=>25668,
 :heap_allocatable_pages=>1112,
 :heap_available_slots=>10007821,
 :heap_live_slots=>10007533,
 :heap_free_slots=>288,
 :heap_final_slots=>0,
 :heap_marked_slots=>5814100,
 :heap_swept_slots=>4651608,
 :heap_eden_pages=>24553,
 :heap_tomb_pages=>0,
 :total_allocated_pages=>24558,
 :total_freed_pages=>5,
 :total_allocated_objects=>10042363,
 :total_freed_objects=>34830,
 :malloc_increase_bytes=>29461328,
 :malloc_increase_bytes_limit=>32225676,
 :minor_gc_count=>13,
 :major_gc_count=>8,
 :remembered_wb_unprotected_objects=>157,
 :remembered_wb_unprotected_objects_limit=>314,
 :old_objects=>5813924,
 :old_objects_limit=>11627848,
 :oldmalloc_increase_bytes=>29461776,
 :oldmalloc_increase_bytes_limit=>24159190}
~ # concat 
~ ruby test.rb
{:count=>446,
 :heap_allocated_pages=>74,
 :heap_sorted_length=>75,
 :heap_allocatable_pages=>0,
 :heap_available_slots=>30164,
 :heap_live_slots=>29231,
 :heap_free_slots=>933,
 :heap_final_slots=>0,
 :heap_marked_slots=>7490,
 :heap_swept_slots=>6010,
 :heap_eden_pages=>72,
 :heap_tomb_pages=>2,
 :total_allocated_pages=>74,
 :total_freed_pages=>0,
 :total_allocated_objects=>10042364,
 :total_freed_objects=>10013133,
 :malloc_increase_bytes=>6992,
 :malloc_increase_bytes_limit=>16777216,
 :minor_gc_count=>440,
 :major_gc_count=>6,
 :remembered_wb_unprotected_objects=>157,
 :remembered_wb_unprotected_objects_limit=>314,
 :old_objects=>7314,
 :old_objects_limit=>14622,
 :oldmalloc_increase_bytes=>7440,
 :oldmalloc_increase_bytes_limit=>32782668}

HParker/array-gc-stats.md