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The sticky partition assignment algorithm described above, as mentioned earlier in this KIP, favors fairness over stickiness (we may call it the fair yet sticky or stickiest fair partition assignment strategy). Therefore, some partitions may change their consumer towards a fair assignment. This alternative strategy is supposedly more complex to implement due to complex nature of calculating the most balanced assignment.
An alternative strategy is to implement it so that stickiness take precedence and all previously assigned partitions are preserved; while the new consumers or partitions that need to be assigned do so towards the fairest possible assignment. We may call this alternative the sticky yet fair or fairest sticky partition assignment strategy. This one strategy would be more efficient as it exhibits less complexity and variance. After all, the previous valid assignments remain as they are and only a few new assignments have to be calculated.
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