Race Condition

What Does Race Condition Mean?

A race condition is a behavior which occurs in software applications or electronic systems, such as logic systems, where the output is dependent on the timing or sequence of other uncontrollable events. Race conditions also occur in software which supports multithreading, use a distributed environment or are interdependent on shared resources. Race conditions often lead to bugs, as these events happen in a manner that the system or programmer never intended for. It can often result in a device crash, error notification or shutdown of the application.


A race condition is also known as a race hazard.

Techopedia Explains Race Condition

A race condition is often classified as either a critical race condition or non-critical race condition. A critical race condition occurs when the sequence in which internal variables change determines the final state of the machine. A non-critical race condition occurs when the sequence in which internal variables’ changes do not have any impact on the final state of the machine. Race conditions are notorious for being difficult to troubleshoot, as reproduction depends on the relative timing between the different elements. Sometimes, especially with software applications, the problem disappears while running in debug mode thanks to an additional logger or debugger.

One of the best ways to avoid a race condition in software and hardware applications is the use of mutual exclusion, which assures that only one process can handle the shared resource at a time, while other processes need to wait. In many cases, Race conditions can be avoided in computing environments with help of serialization of memory or storage access. Another technique that is recommended, especially in software applications, is to analyze and avoid the race condition in the software design itself. There are certain software tools available which help in the detection of race conditions for software.


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Margaret Rouse
Technology Expert

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.