Memory System: Cache, DRAM, Disk

简介：
本课程将深入探讨计算机系统中的存储层次结构，涵盖高速缓存（Cache）、动态随机存取内存（DRAM）及磁盘存储的工作原理、性能特征及其相互间的协同作用。 A storage system typically includes multiple levels of memory designed to optimize data access speed and efficiency. At the top level, there is cache, which is a small but very fast type of memory used for temporary storage of frequently accessed data. Cache reduces latency by providing quick access to commonly requested information. Beneath cache lies DRAM (Dynamic Random Access Memory), which serves as primary system memory. Unlike cache, DRAM retains data only while powered on and has slower access times compared to cache but is significantly larger in capacity. This makes it suitable for storing active applications and frequently used files. At the bottom of this hierarchy is magnetic disk storage, such as hard drives or SSDs (Solid State Drives). These provide much greater storage capacities than DRAM at a lower cost per gigabyte, albeit with slower access times compared to both cache and DRAM. Magnetic disks are ideal for long-term data retention and less frequently accessed files. Together, these components form a tiered memory system that balances speed and capacity requirements effectively.