Overview
While a 'Store Buffer' is usually internal to the CPU core, a 'Write Buffer' often sits between the cache and the main memory (or between a controller and a disk). It aggregates multiple small writes into larger, more efficient bursts.
Benefits
- Latency Hiding: The processor can continue working as soon as the data is in the buffer.
- Bandwidth Efficiency: Reduces the number of individual transactions on the memory bus.
Risk
If the system loses power before the buffer is 'flushed' to permanent storage, data can be lost. This is why high-end storage controllers often have battery-backed write buffers.