System Idle Process is when the system is idle or doing nothing.
2 : to run at low power and often disconnected usually so that power is
not used for useful work
<the engine is idling>
Definition of idle - Merriam-Webster Online Dictionary
System Idle Process reference...
[[Idle: This is a generic process that is used when no other program or
process is requiring CPU resources. It is not a bad thing if it is using
99% of your CPU! This process is a 16 k loop that the CPU processes
while it is not doing "anything" else. If you computer is called upon to
do any other task than nothing, the idle process allows that to happen
and the % used will decrease accordingly. You can not disable the idle
process. If it is using 97% CPU, which only means that the other 3% is
used by real programs. If your idle process is constantly at a low rate
(for example, 3%) something else, an application or process is using the
CPU.]]
http://web.archive.org/web/20041125021602/www.blackviper.com/WinXP/strangeservice.htm
[[Note The System Idle Process indicates the unused percentage of the
CPU.]] Task Manager may not calculate CPU usage correctly on Windows
2000, Windows Server 2003, or Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;873289
[[System Idle Process - You cannot end this process from Task Manager.
* This process is a single thread running on each processor, which has
the sole task of accounting for processor time when the system isn't
processing other threads. In Task Manager, expect this process to
account for the majority of processor time. ]]
Default Processes in Windows 2000
http://support.microsoft.com/default.aspx?scid=kb;en-us;263201
[[Description:
the System Idle Process is not a process, more a counter which is
displayed in WinTasks used for measuring how much idle time the CPU is
having at any particular time. This counter will display how much CPU
Resources, as a percentage are 'idle' and available for use. Cannot be
killed]]
http://www.liutilities.com/products/wintaskspro/processlibrary/System Idle Process/
[[System Idle Process
An option in the Windows XP Task Manager that indicates what percentage
of time the CPU is currently doing nothing but waiting for work. If no
applications are running that the user is aware of (although there may
always be some tasks running in the background), the percentage can be in
the high 90s. ]]
http://www.answers.com/topic/system-idle-process
[[System idle process
In computing, The System Idle Process is a process in the Microsoft
Windows operating system that displays, as a percentage, how much CPU
resources are "idle" and available for use at any given time. The name
of this "process" may be a misnomer, however, as the System Idle Process
is more of a counter and less of a process that actually uses the
resource percentage that it displays.]]
http://www.answers.com/topic/system-idle-process