对象从堆中分配；因此，使用的和空闲的堆内存数量是两个非常重要的统计信息。

Objects are allocated from the heap; thus the amount of heap memory both used and free are two very important statistics.

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在使用对象池时，分配、初始化、回收和终结只发生一次，从而减少了内存使用和所需的处理时间。

When using an object pool, the allocation, initialization, collection, and finalization only occur once, reducing both the memory usage and the processing time that is required.

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希望分配了大量连续内存区域但这些内存不马上同时使用的程序常常结合使用保留内存和提交内存。

Programs that want to allocate a large and contiguous area of memory but don't need it all immediately often use a combination of reserved and committed memory.

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