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63 lines
2.0 KiB
Lua
63 lines
2.0 KiB
Lua
--[[
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"semi-manual" garbage collection
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specify a time budget and a memory ceiling per call.
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called once per frame, this will spread any big collections
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over several frames, and "catch up" when there is too much
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work to do.
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This keeps GC time burden much more predictable.
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The memory ceiling provides a safety backstop.
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if exceeded it will trigger a "full" collection, and this will
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hurt performance - you'll notice the hitch. If you hit your ceiling,
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it indicates you likely need to either find a way to generate less
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garbage, or spend more time each frame collecting.
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the function instructs the garbage collector only as small a step
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as possible each iteration. this prevents the "spiky" collection
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patterns, though with particularly large sets of tiny objects,
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the start of a collection can still take longer than you might like.
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default values:
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time_budget - 1ms (1e-3)
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adjust down or up as needed. games that generate more garbage
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will need to spend longer on gc each frame.
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memory_ceiling - unlimited
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a good place to start might be something like 64mb, though some games
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will need much more. remember, this is lua memory, not the total memory
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consumption of your game.
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disable_otherwise - false
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disabling the gc completely is dangerous - any big allocation
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event (eg - level gen) could push you to an out of memory
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situation and crash your game. test extensively before you
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ship a game with this set true.
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]]
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return function(time_budget, memory_ceiling, disable_otherwise)
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time_budget = time_budget or 1e-3
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memory_ceiling = memory_ceiling or math.huge
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local max_steps = 1000
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local steps = 0
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local start_time = love.timer.getTime()
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while
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love.timer.getTime() - start_time < time_budget and
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steps < max_steps
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do
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collectgarbage("step", 1)
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steps = steps + 1
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end
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--safety net
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if collectgarbage("count") / 1024 > memory_ceiling then
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collectgarbage("collect")
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end
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--don't collect gc outside this margin
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if disable_otherwise then
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collectgarbage("stop")
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end
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end
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