https://www.pistack.xyz/tags/page-cache/ Recent content in Page-Cache on Pi Stack Hugo en-us Sat, 23 May 2026 00:00:00 +0000 https://www.pistack.xyz/posts/2026-05-23-linux-page-cache-inspection-pcstat-vmtouch-fincore-guide/ Sat, 23 May 2026 00:00:00 +0000 https://www.pistack.xyz/posts/2026-05-23-linux-page-cache-inspection-pcstat-vmtouch-fincore-guide/ <p>The Linux page cache is one of the most powerful performance optimizations built into the kernel — it automatically caches recently accessed file data in unused RAM, dramatically accelerating repeat reads without any application changes. But this invisible caching layer can also mask memory pressure, cause confusion about &ldquo;missing&rdquo; RAM, and lead to suboptimal I/O patterns when hot data gets evicted. Three tools help administrators inspect and manage the page cache: <strong>pcstat</strong> (page cache statistics), <strong>vmtouch</strong> (virtual memory touch), and <strong>fincore</strong> (file in-core). Understanding which files are cached, how much memory they consume, and how to control caching behavior is essential for tuning self-hosted server performance.</p>