Subject: Operating System

Topic: STORAGE MANAGEMENT

Difficulty: Hard

A disk cache is a cache memory that is used to speed up the process of storing and accessing data from the host hard disk. It enables faster processing of reading/writing, commands and other input and output process between the hard disk, the memory and computing components.

A disk cache is also referred to as a disk buffer and cache buffer.A disk cache is a mechanism for improving the time it takes to read from or write to a hard disk.

Today, the disk cache is usually included as part of the hard disk. A disk cache can also be a specified portion of random access memory (RAM).

The disk cache holds data that has recently been read and, in some cases, adjacent data areas that are likely to be accessed next. Write caching is also provided with some disk caches.A disk cache is an integrated part of the hard disk and is a standard feature of most hard disk drives.

The size of disk cache ranges from 128 MB in standard disks to 1 GB in solid state disks.Typically, a disk cache stores the most recent and frequently used programs and data.

When a user or program requests data, the operating system first reviews the disk cache. If the data is found, the OS and memory quickly deliver the data to the program.

A disk cache can also be soft disk cache when it’s implemented on the RAM rather than the host/native hard disk.