# Page Cache Status: Seedling The page cache is memory the Linux kernel uses to cache file-backed data. ## Mental Model Disk is slow compared to memory. When a process reads file data, Linux can keep that data in memory so future reads avoid going back to disk. Writes can also interact with the page cache before data is eventually flushed. ## Why It Matters The page cache affects: - File read performance. - Memory usage. - Benchmark interpretation. - Database behavior. - Production debugging. ## Related - [[Articles/Tracing System Calls at a High Level]] - [[Topics/Linux & Systems]] - [[Field Notes/File Descriptor]]