It supports both local disk caching as well as caching in memory.

它既支持本地磁盘缓存，也支持内存中的缓存。

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Disk caching reduces the in-memory footprint while creating a PDF, but is slower.

虽然在创建P DF时，磁盘缓存减少了内存占用，但是速度变得更慢了。

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For instance, you can allocate memory for caching, which reduces disk access, or access resources over the network rather than reading off the local disk.

例如，可以为缓存分配内存，这可以减少磁盘访问或通过网络的资源访问。

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Write caching could allow the hard disk drive to stay in a lower power non-spinning state for longer periods of time, extending battery life for the notebook computer.

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Perhaps the biggest gain may be in dual storage computers where a flash memory device is used for storing operating systems, software and frequently accessed content (and maybe even for write caching) while a hard disk drive provides much less expensive mass storage of user data.

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Of course the total energy used by a hard disk drive depends upon the actual usage and power saving modes, and caching of data can reduce the energy used by a HDD in a computer system.

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