What is initial program load (IPL)? - Definition from WhatIs.com


initial program load (IPL)

Part of the Operating systems glossary:

IPL (initial program load) is a mainframe term for the loading of the operating system into the computer's main memory . A mainframe operating system (such as OS/390) contains many megabytes of code that is customized by each installation, requiring some time to load the code into the memory. On a personal computer, booting or re-booting (re-starting) is the equivalent to IPLing (the term is also used as a verb) .

In earlier operating systems, when you added devices to the hardware system, you had to stop the system, change the configuration file, and then "re-IPL," an activity that meant the system would be unavailable for some period of time. Today's systems provide dynamic reconfiguration so that the system can keep running.

This was last updated in March 2011
Posted by: Margaret Rouse

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