Particle buffers

are a new mechanism designed to overcome the limitations of the contiguous
buffering system. Instead of allocating a contiguous block, particle-based systems allocate
small, discontiguous blocks of memory called particles, which are then linked together to form
a logically contiguous packet buffer. These packet buffers are therefore spread across multiple
physical particles in different locations.
The advantage of this method is that no buffers of specific sizes need to be allocated in
advance; instead, buffers are created as needed, and of the optimum size (within the limits of the
particle sizes, which are usually split into pools of 128 and/or 512 bytes).
Figure 21.6 shows how the use of particles may not completely eliminate waste, but sure cuts
it down to a minimum!