mirror of
https://github.com/ruby/ruby.git
synced 2022-11-09 12:17:21 -05:00
3ef4db15e9
This commit adds the new method `GC.compact` and compacting GC support. Please see this issue for caveats: https://bugs.ruby-lang.org/issues/15626 [Feature #15626] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67479 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
95 lines
2.5 KiB
Ruby
95 lines
2.5 KiB
Ruby
# frozen_string_literal: true
|
|
require 'test/unit'
|
|
require 'fiddle'
|
|
|
|
class TestGCCompact < Test::Unit::TestCase
|
|
if Fiddle::SIZEOF_LONG == Fiddle::SIZEOF_VOIDP
|
|
def memory_location(obj)
|
|
(Fiddle.dlwrap(obj) >> 1)
|
|
end
|
|
elsif Fiddle::SIZEOF_LONG_LONG == Fiddle::SIZEOF_VOIDP
|
|
def memory_location(obj)
|
|
(Fiddle.dlwrap(obj) >> 1) / 2
|
|
end
|
|
else
|
|
raise "Not supported"
|
|
end
|
|
|
|
def assert_object_ids(list)
|
|
same_count = list.find_all { |obj|
|
|
memory_location(obj) == obj.object_id
|
|
}.count
|
|
list.count - same_count
|
|
end
|
|
|
|
def big_list
|
|
1000.times.map { Object.new } # likely next to each other
|
|
end
|
|
|
|
# Find an object that's allocated in a slot that had a previous
|
|
# tenant, and that tenant moved and is still alive
|
|
def find_object_in_recycled_slot(addresses)
|
|
new_object = nil
|
|
|
|
loop do
|
|
new_object = Object.new
|
|
if addresses.include? memory_location(new_object)
|
|
break
|
|
end
|
|
end
|
|
|
|
new_object
|
|
end
|
|
|
|
def test_find_collided_object
|
|
list_of_objects = big_list
|
|
|
|
ids = list_of_objects.map(&:object_id) # store id in map
|
|
addresses = list_of_objects.map(&self.:memory_location)
|
|
|
|
# All object ids should be equal
|
|
assert_equal 0, assert_object_ids(list_of_objects) # should be 0
|
|
|
|
GC.compact
|
|
|
|
# Some should have moved
|
|
assert_operator assert_object_ids(list_of_objects), :>, 0
|
|
|
|
new_ids = list_of_objects.map(&:object_id)
|
|
|
|
# Object ids should not change after compaction
|
|
assert_equal ids, new_ids
|
|
|
|
new_tenant = find_object_in_recycled_slot(addresses)
|
|
assert new_tenant
|
|
|
|
# This is the object that used to be in new_object's position
|
|
previous_tenant = list_of_objects[addresses.index(memory_location(new_tenant))]
|
|
|
|
assert_not_equal previous_tenant.object_id, new_tenant.object_id
|
|
|
|
# Should be able to look up object by object_id
|
|
assert_equal new_tenant, ObjectSpace._id2ref(new_tenant.object_id)
|
|
|
|
# Should be able to look up object by object_id
|
|
assert_equal previous_tenant, ObjectSpace._id2ref(previous_tenant.object_id)
|
|
|
|
int = (new_tenant.object_id >> 1)
|
|
# These two should be the same! but they are not :(
|
|
assert_equal int, ObjectSpace._id2ref(int.object_id)
|
|
end
|
|
|
|
def test_many_collisions
|
|
list_of_objects = big_list
|
|
ids = list_of_objects.map(&:object_id)
|
|
addresses = list_of_objects.map(&self.:memory_location)
|
|
|
|
GC.compact
|
|
|
|
new_tenants = 10.times.map {
|
|
find_object_in_recycled_slot(addresses)
|
|
}
|
|
|
|
assert_operator GC.stat(:object_id_collisions), :>, 0
|
|
end
|
|
end
|