Write Back

Definitions

1. A caching strategy where writes update only the cache initially, marking the cache line as dirty, and the modified data is flushed to the backing store (main memory or disk) only when the cache line is evicted or explicitly flushed — reducing write traffic at the cost of requiring careful consistency management.

   In plain English: A speed trick where changes are saved to a fast cache first and only written to slower storage later when necessary.

   Example: "The CPU uses write-back caching, so you need a memory barrier before the DMA transfer or the device will read stale data from RAM."

Related Terms

• Swap
• DMA
• Cache
• Memory Allocation
• Weak Reference
• Apache Arrow
• LRU Cache
• Page Cache
• Stack Frame
• Write Through
• Cache Eviction