WorstFit is in contrast to BestFit, instead always choosing the worst possible allocation. So if you have 10, 20 and 30 byte spaces free and you want to allocate 9 bytes of space you will chop some out of the 30 byte space, leaving 10,20 and 21 byte spaces available. This doesn't have the disadvantage that BestFit has of leaving lots of useless tiny allocations. It however has the disadvantage that you tend to have very few very large allocations after a few allocations.
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