The read ahead buffer and sliding window is not required during decoding. The first 10 a's are literal bytes, so they are decoding as is.
解码过程不需要读取前部数据缓冲和幻灯片式窗口。开始的十个“A”都是原封未动的字节，所以就按照原样解码。
Further, applications that might benefit from having a file system read ahead or high buffer cache hit rates might actually see performance degradation.
而且，对于那些受益于文件系统预读功能或者较高缓冲区缓存命中率的应用程序，可能会出现性能的降低。
For the buffer processing, the MFC treats a zero-size data request as a no-op, so I can go ahead and issue requests even if there is no data to read.
对于缓冲区处理，MFC 将大小为零的数据请求当作无操作来对待，所以即使没有数据可读取了，也可以继续发出请求。
You'd have to write a handler to build what amounts to an in-memory buffer to keep up with what's already been read; then you'd need some code to read ahead as well.
所以，必须要编写一个相当于内存缓冲器的处理程序来记录已读的内容，也同时需要编写一些代码进行提前读。
You'd have to write a handler to build what amounts to an in-memory buffer to keep up with what's already been read; then you'd need some code to read ahead as well.
所以，必须要编写一个相当于内存缓冲器的处理程序来记录已读的内容，也同时需要编写一些代码进行提前读。
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