personally, I think tuning is to achieve the performance target you want by adjusting the jvm parameters. This performance indicator is more subjective, such as jvm will not know whether you want better response time or better throughput. You might say I want the best of both, which is, of course, the ideal scenario, but because response time and throughput are generally the opposite, jvm normally can only balance the two. Through manual tuning, we can tilt a certain index pertinently, and we can achieve more flexible control by setting different gc strategies, different memory strategies and so on.

Parallel Scavenge is enabled by default. UseAdaptiveSizePolicy, has a certain automatic tuning function. For more information, please see Ergonomics for
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