If you see that the middle tier is becoming the bottleneck, you may have to add more no. of application servers and same is the case with the data tier.

如果你发现中间层正在变成瓶颈，你就必须增加应用服务器的数量，数据层也是同样的状况。

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The application has no knowledge of Gridscale or the transactional tier.

应用程序不知道Gridscale或事务层。

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REST does not necessarily mean there is no state on the middle tier; the state to fulfill the request for a resource is not dependent on that state.

REST并不一定就意味着在中间层没有任何状态；为实现对某资源的请求的这个状态并不依赖于该状态。

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Though no top-tier record company has supported the MP3 format, Sub Pop joins a growing list of independent record labels offering MP3 versions of their artists' recordings.

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What will happen if the returns no longer justify top-tier budgets?

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Yet early Chinese OEMs offered only low-tier phones with no attempts at branding or differentiation.

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