Hierarchical Storage Management

Why Trust Techopedia

What Does Hierarchical Storage Management Mean?

Hierarchical storage management (HSM) is a data storage software tool that is used to transparently move data between various types of storage media. The HSM technique is designed to automate the migration and retrieval of data between expensive storage media such as hard disk drives and low-cost media such as optical disks and magnetic tapes.


The concept of HSM technology is similar to a computer’s memory cache, where the most actively used data are stored on expensive static random access memory (SRAM) and the less frequently accessed data are stored on a much slower dynamic random access memory (DRAM).

HSM technology has been widely implemented by IBM in the mainframe environment. HSM is also known as tiered storage.

Techopedia Explains Hierarchical Storage Management

In heterogeneous computing environments, hierarchical storage management software provides a way to move the data between storage devices that are organized in a descending hierarchy level with respect to cost and performance. The HSM software automatically moves the data on the storage device that offers the optimum cost/performance ratio for that data. All the data stored in the repository appear online to the user, regardless of whether they are stored as online, near-line or offline. The HSM tool monitors data use, keeping frequently accessed files at online level. The less frequently accessed files are moved to slower devices. The most active and frequently accessed files are left on expensive storage devices until they are disused and again moved back to less expensive optical or tape devices.

The advantages of HSM technology include:

  • Large amount of data can be stored in a relatively small storage space
  • Reduced data storage costs
  • Simplified data retrieval from lower level devices
  • Transparency

The HSM technology is implemented on Solaris, HP-UX and Linux.


Related Terms

Margaret Rouse
Senior Editor
Margaret Rouse
Senior Editor

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.