Re: Quering "System Idle Process"

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"m4rky" <m4rky@xxxxxxxxxxxxxxx> wrote in message
news:156FE474-AB32-47AD-99FD-647F8632F2F0@xxxxxxxxxxxxx
Thanks for your help. Although, a pseudo-process is hard to
explain to those who ask me... was it a thread or a kernel driver or
a DLL?

Realize that a "process" is just a data structure in the kernel, mainly
for maintaining an address space and a collection of threads. In user
mode, this structure is created by CreateProcess call, which insists on
associating it with an EXE. But kernel has direct access to its own data
structures. When the OS is loaded, kernel creates an instance of
"process" data structure not backed by any EXE, to hold a collection of
all the threads kernel itself creates - the System process. This is done
for convenience, to make handling of all threads uniform.

Similarly, again for convenience, kernel creates System Idle Process.
This one hosts a single thread, of lowest possible priority, that simply
zeroes out unused memory pages while the processor has nothing better to
do. This simplifies the thread scheduler, which now doesn't have to deal
with an edge condition of not having any threads to schedule.

I believe it has to have a parent process like the rest.

If every process has to have a parent process, what would be the parent
process of the parent process? Would it in turn have its own parent? And
that one in turn should have a parent, right? You get my drift.
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


.

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