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Buffer management

Circular buffers in FFPF have two indices to indicate the current read and write positions. These are known as \ensuremath{R} and \ensuremath{W}, respectively. Whenever \ensuremath{W} catches up with \ensuremath{R}, the buffer is full. The way in which the system handles this case is defined by the buffer management system (BMS). The modular design of FFPF allows different BMSs to be used. The administrator chooses the BMS at startup time. The optimal choice depends on the mix of applications that will be executed and their relative importance. Currently, two BMSs have been defined. The first is known as `slow reader preference' and is commonly used in existing systems. The second is known as `fast reader preference' and is a novel way of ensuring that fast readers are not slowed down by tardy applications.


Herbert Bos 2004-10-06