Perceived performance
Encyclopedia
Perceived performance, in computer engineering
, refers to how quickly a software feature appears to perform its task. The concept applies mainly to user acceptance aspects.
The amount of time an application takes to start up, or a file to download, is not made faster by showing a startup screen (see Splash screen
) or a file progress dialog box
. However, it satisfies some human needs: it appears faster to the user as well as providing a visual cue to let them know the system is handling their request.
In most cases, increasing real performance increases perceived performance, but when real performance cannot be increased due to physical limitations, techniques can be used to increase perceived performance at the cost of marginally decreasing real performance. for example, drawing and refreshing a progress bar while loading a file satisfies the user who is watching, but steals time from the process that is actually loading the file, but usually this is only a very small amount of time. All such techniques must exploit the inability of the user to accurately judge real performance, or they would be considered detrimental to performance.
Techniques for improving perceived performance may include more than just decreasing the delay between the user's request and visual feedback. Sometimes an increase in delay can be perceived as a performance improvement, such as when a variable controlled by the user is set to a running average of the users input. This can give the impression of smoother motion, but the controlled variable always reaches the desired value a bit late. Since it smooths out hi-frequency jitter, when the user is attempting to hold the value constant, they may feel like they are succeeding more readily. This kind of compromise would be appropriate for control of a sniper rifle in a video game.
A technique to measure and interpret perceived performance remote systems is shown in a 2003 and updated in 2005 for virtual machines.
Computer engineering
Computer engineering, also called computer systems engineering, is a discipline that integrates several fields of electrical engineering and computer science required to develop computer systems. Computer engineers usually have training in electronic engineering, software design, and...
, refers to how quickly a software feature appears to perform its task. The concept applies mainly to user acceptance aspects.
The amount of time an application takes to start up, or a file to download, is not made faster by showing a startup screen (see Splash screen
Splash screen
A splash screen is an image that appears while a game or program is loading. It may also be used to describe an introduction page on a website. Splash screens sometimes do not cover the entire screen, but only a rectangle near the center...
) or a file progress dialog box
Dialog box
In a graphical user interface of computers, a dialog box is a type of window used to enable reciprocal communication or "dialog" between a computer and its user. It may communicate information to the user, prompt the user for a response, or both...
. However, it satisfies some human needs: it appears faster to the user as well as providing a visual cue to let them know the system is handling their request.
In most cases, increasing real performance increases perceived performance, but when real performance cannot be increased due to physical limitations, techniques can be used to increase perceived performance at the cost of marginally decreasing real performance. for example, drawing and refreshing a progress bar while loading a file satisfies the user who is watching, but steals time from the process that is actually loading the file, but usually this is only a very small amount of time. All such techniques must exploit the inability of the user to accurately judge real performance, or they would be considered detrimental to performance.
Techniques for improving perceived performance may include more than just decreasing the delay between the user's request and visual feedback. Sometimes an increase in delay can be perceived as a performance improvement, such as when a variable controlled by the user is set to a running average of the users input. This can give the impression of smoother motion, but the controlled variable always reaches the desired value a bit late. Since it smooths out hi-frequency jitter, when the user is attempting to hold the value constant, they may feel like they are succeeding more readily. This kind of compromise would be appropriate for control of a sniper rifle in a video game.
A technique to measure and interpret perceived performance remote systems is shown in a 2003 and updated in 2005 for virtual machines.