Most custom sweepers observe some model object, and based on changes, fire logic to expire one or more cache pages.

多数定制清理器都会观察某些模型对象，并根据更改击发逻辑来使一个或多个缓存页面到期失效。

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The 30 day cache solves the user-error problem and the fact that data is stored on the Internet solves the fire/flood/theft issue (where USB or network drives may also be affected).

30天的缓存解决了用户错误的问题，同时由于数据存储在互联网上，也就避免了火灾、洪水和盗窃的问题（而USB 和网络硬盘是无法避免这些问题的）。

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When that event fires, the sweeper will fire, and can invalidate selected pages in the cache.

当此事件击发时，清理器也会击发，并可让缓存内的特定页面到期失效。

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As a result, the next page a Kindle Fire customer is likely to visit will already be available locally in the device cache, enabling instant rendering to the screen.

ENGADGET: Amazon Silk browser spins a faster mobile web, courtesy of cloud servers (video)