[COFF] Terminology query - 'system process'?

[COFF] Terminology query - 'system process'?

[Noel Chiappa]

So Lars Brinkhoff and I were chatting about daemons:

  https://gunkies.org/wiki/Talk:Daemon

and I pointed out that in addition to 'standard' daemons (e.g. the printer
spooler daemon, email daemon, etc, etc) there are some other things that are
daemon-like, but are fundamentally different in major ways (explained later
below). I dubbed them 'system processes', but I'm wondering if ayone knows if
there is a standard term for them? (Or, failing that, if they have a
suggestion for a better name?)


Early UNIX is one of the first systems to have one (process 0, the "scheduling (swapping)
process"), but the CACM "The UNIX Time-Sharing System" paper:

  https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf

doesn't even mention it, so no guidance there. Berkeley UNIX also has one,
mentioned in "Design and Implementation of the Berkeley Virtual Memory
Extensions to the UNIX Operating System":

  http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf

where it is called the "pageout daemon".("During system initialization, just
before the init process is created, the bootstrapping code creates process 2
which is known as the pageout daemon. It is this process that .. writ[es]
back modified pages. The process leaves its normal dormant state upon being
waken up due to the memory free list size dropping below an upper
threshold.") However, I think there are good reasons to dis-favour the term
'daemon' for them.


For one thing, typical daemons look (to the kernel) just like 'normal'
processes: their object code is kept in a file, and is loaded into the
daemon's process when it starts, using the same mechanism that 'normal'
processes use for loading their code; daemons are often started long after
the kernel itself is started, and there is usually not a special mechanism in
the kernel to start daemons (on early UNIXes, /etc/rc is run by the 'init'
process, not the kernel); daemons interact with the kernel through system
calls, just like 'ordinary' processes; the daemon's process runs in 'user'
CPU mode (using the same standard memory mapping mechanisms, just like
blah-blah).

'System processes' do none of these things: their object code is linked into
the monolithic kernel, and is thus loaded by the bootstrap; the kernel
contains special provision for starting the system process, which start as
the kernel is starting; they don't do system calls, just call kernel routines
directly; they run in kernel mode, using the same memory mapping as the
kernel itself; etc, etc.

Another important point is that system processes are highly intertwined with
the operation of the kernel; without the system process(es) operating
correctly, the operation of the system will quickly grind to a halt. The loss
of ordinary' daemons is usually not fatal; if the email daemon dies, the
system will keep running indefinitely. Not so, for the swapping process, or
the pageout daemon


Anyway, is there a standard term for these things? If not, a better name than
'system process'?

	Noel

[COFF] Re: Terminology query - 'system process'?

[Bakul Shah]

I remember calling them kernel processes as they had no code running in user mode. Not sure now of the year but sometime in ‘80s. Now I’d probably call them kernel threads as they don’t have a separate address space.

> On Dec 14, 2023, at 1:48 PM, jnc@mercury.lcs.mit.edu wrote:
> 
> So Lars Brinkhoff and I were chatting about daemons:
> 
>  https://gunkies.org/wiki/Talk:Daemon
> 
> and I pointed out that in addition to 'standard' daemons (e.g. the printer
> spooler daemon, email daemon, etc, etc) there are some other things that are
> daemon-like, but are fundamentally different in major ways (explained later
> below). I dubbed them 'system processes', but I'm wondering if ayone knows if
> there is a standard term for them? (Or, failing that, if they have a
> suggestion for a better name?)
> 
> 
> Early UNIX is one of the first systems to have one (process 0, the "scheduling (swapping)
> process"), but the CACM "The UNIX Time-Sharing System" paper:
> 
>  https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf
> 
> doesn't even mention it, so no guidance there. Berkeley UNIX also has one,
> mentioned in "Design and Implementation of the Berkeley Virtual Memory
> Extensions to the UNIX Operating System":
> 
>  http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf
> 
> where it is called the "pageout daemon".("During system initialization, just
> before the init process is created, the bootstrapping code creates process 2
> which is known as the pageout daemon. It is this process that .. writ[es]
> back modified pages. The process leaves its normal dormant state upon being
> waken up due to the memory free list size dropping below an upper
> threshold.") However, I think there are good reasons to dis-favour the term
> 'daemon' for them.
> 
> 
> For one thing, typical daemons look (to the kernel) just like 'normal'
> processes: their object code is kept in a file, and is loaded into the
> daemon's process when it starts, using the same mechanism that 'normal'
> processes use for loading their code; daemons are often started long after
> the kernel itself is started, and there is usually not a special mechanism in
> the kernel to start daemons (on early UNIXes, /etc/rc is run by the 'init'
> process, not the kernel); daemons interact with the kernel through system
> calls, just like 'ordinary' processes; the daemon's process runs in 'user'
> CPU mode (using the same standard memory mapping mechanisms, just like
> blah-blah).
> 
> 'System processes' do none of these things: their object code is linked into
> the monolithic kernel, and is thus loaded by the bootstrap; the kernel
> contains special provision for starting the system process, which start as
> the kernel is starting; they don't do system calls, just call kernel routines
> directly; they run in kernel mode, using the same memory mapping as the
> kernel itself; etc, etc.
> 
> Another important point is that system processes are highly intertwined with
> the operation of the kernel; without the system process(es) operating
> correctly, the operation of the system will quickly grind to a halt. The loss
> of ordinary' daemons is usually not fatal; if the email daemon dies, the
> system will keep running indefinitely. Not so, for the swapping process, or
> the pageout daemon
> 
> 
> Anyway, is there a standard term for these things? If not, a better name than
> 'system process'?
> 
>    Noel

[COFF] Re: Terminology query - 'system process'?

[Warner Losh]

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When shutting down, FreeBSD refers to them as:
kern/kern_shutdown.c: printf("Waiting (max %d seconds) for system process
`%s' to stop... ",
kern/kern_shutdown.c: printf("Waiting (max %d seconds) for system thread
`%s' to stop... ",

However, a number of places, including the swap daemon, still refer to
things as this daemon
or that daemon (page demon being top of the list, but there's the buf
daemon, the vmdaemon
that handles swapping (as opposed to paging), the update daemon, etc.

Warner

On Thu, Dec 14, 2023 at 3:06 PM Bakul Shah <bakul@iitbombay.org> wrote:

> I remember calling them kernel processes as they had no code running in
> user mode. Not sure now of the year but sometime in ‘80s. Now I’d probably
> call them kernel threads as they don’t have a separate address space.
>
> > On Dec 14, 2023, at 1:48 PM, jnc@mercury.lcs.mit.edu wrote:
> >
> > So Lars Brinkhoff and I were chatting about daemons:
> >
> >  https://gunkies.org/wiki/Talk:Daemon
> >
> > and I pointed out that in addition to 'standard' daemons (e.g. the
> printer
> > spooler daemon, email daemon, etc, etc) there are some other things that
> are
> > daemon-like, but are fundamentally different in major ways (explained
> later
> > below). I dubbed them 'system processes', but I'm wondering if ayone
> knows if
> > there is a standard term for them? (Or, failing that, if they have a
> > suggestion for a better name?)
> >
> >
> > Early UNIX is one of the first systems to have one (process 0, the
> "scheduling (swapping)
> > process"), but the CACM "The UNIX Time-Sharing System" paper:
> >
> >  https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf
> >
> > doesn't even mention it, so no guidance there. Berkeley UNIX also has
> one,
> > mentioned in "Design and Implementation of the Berkeley Virtual Memory
> > Extensions to the UNIX Operating System":
> >
> >  http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf
> >
> > where it is called the "pageout daemon".("During system initialization,
> just
> > before the init process is created, the bootstrapping code creates
> process 2
> > which is known as the pageout daemon. It is this process that .. writ[es]
> > back modified pages. The process leaves its normal dormant state upon
> being
> > waken up due to the memory free list size dropping below an upper
> > threshold.") However, I think there are good reasons to dis-favour the
> term
> > 'daemon' for them.
> >
> >
> > For one thing, typical daemons look (to the kernel) just like 'normal'
> > processes: their object code is kept in a file, and is loaded into the
> > daemon's process when it starts, using the same mechanism that 'normal'
> > processes use for loading their code; daemons are often started long
> after
> > the kernel itself is started, and there is usually not a special
> mechanism in
> > the kernel to start daemons (on early UNIXes, /etc/rc is run by the
> 'init'
> > process, not the kernel); daemons interact with the kernel through system
> > calls, just like 'ordinary' processes; the daemon's process runs in
> 'user'
> > CPU mode (using the same standard memory mapping mechanisms, just like
> > blah-blah).
> >
> > 'System processes' do none of these things: their object code is linked
> into
> > the monolithic kernel, and is thus loaded by the bootstrap; the kernel
> > contains special provision for starting the system process, which start
> as
> > the kernel is starting; they don't do system calls, just call kernel
> routines
> > directly; they run in kernel mode, using the same memory mapping as the
> > kernel itself; etc, etc.
> >
> > Another important point is that system processes are highly intertwined
> with
> > the operation of the kernel; without the system process(es) operating
> > correctly, the operation of the system will quickly grind to a halt. The
> loss
> > of ordinary' daemons is usually not fatal; if the email daemon dies, the
> > system will keep running indefinitely. Not so, for the swapping process,
> or
> > the pageout daemon
> >
> >
> > Anyway, is there a standard term for these things? If not, a better name
> than
> > 'system process'?
> >
> >    Noel
>

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[COFF] Re: Terminology query - 'system process'?

[Clem Cole]

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I don't know of a standard name.   We used to call the kernel processes or
kernel threads also.  For instance, in the original Masscomp EFS code, we
had a handful of processes that got forked after the pager using kernel
code.  Since the basic UNIX read/write from the user space scheme is
synchronous, the premade pool of kernel processes was dispatched as needed
when we listened for asynchronous remote requests for I/O. This is similar
to the fact that asynchronous devices from serial or network interfaces
need a pool of memory to stuff things into since you never know ahead of
time when it will come.
ᐧ

On Thu, Dec 14, 2023 at 4:48 PM Noel Chiappa <jnc@mercury.lcs.mit.edu>
wrote:

> So Lars Brinkhoff and I were chatting about daemons:
>
>   https://gunkies.org/wiki/Talk:Daemon
>
> and I pointed out that in addition to 'standard' daemons (e.g. the printer
> spooler daemon, email daemon, etc, etc) there are some other things that
> are
> daemon-like, but are fundamentally different in major ways (explained later
> below). I dubbed them 'system processes', but I'm wondering if ayone knows
> if
> there is a standard term for them? (Or, failing that, if they have a
> suggestion for a better name?)
>
>
> Early UNIX is one of the first systems to have one (process 0, the
> "scheduling (swapping)
> process"), but the CACM "The UNIX Time-Sharing System" paper:
>
>   https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf
>
> doesn't even mention it, so no guidance there. Berkeley UNIX also has one,
> mentioned in "Design and Implementation of the Berkeley Virtual Memory
> Extensions to the UNIX Operating System":
>
>   http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf
>
> where it is called the "pageout daemon".("During system initialization,
> just
> before the init process is created, the bootstrapping code creates process
> 2
> which is known as the pageout daemon. It is this process that .. writ[es]
> back modified pages. The process leaves its normal dormant state upon being
> waken up due to the memory free list size dropping below an upper
> threshold.") However, I think there are good reasons to dis-favour the term
> 'daemon' for them.
>
>
> For one thing, typical daemons look (to the kernel) just like 'normal'
> processes: their object code is kept in a file, and is loaded into the
> daemon's process when it starts, using the same mechanism that 'normal'
> processes use for loading their code; daemons are often started long after
> the kernel itself is started, and there is usually not a special mechanism
> in
> the kernel to start daemons (on early UNIXes, /etc/rc is run by the 'init'
> process, not the kernel); daemons interact with the kernel through system
> calls, just like 'ordinary' processes; the daemon's process runs in 'user'
> CPU mode (using the same standard memory mapping mechanisms, just like
> blah-blah).
>
> 'System processes' do none of these things: their object code is linked
> into
> the monolithic kernel, and is thus loaded by the bootstrap; the kernel
> contains special provision for starting the system process, which start as
> the kernel is starting; they don't do system calls, just call kernel
> routines
> directly; they run in kernel mode, using the same memory mapping as the
> kernel itself; etc, etc.
>
> Another important point is that system processes are highly intertwined
> with
> the operation of the kernel; without the system process(es) operating
> correctly, the operation of the system will quickly grind to a halt. The
> loss
> of ordinary' daemons is usually not fatal; if the email daemon dies, the
> system will keep running indefinitely. Not so, for the swapping process, or
> the pageout daemon
>
>
> Anyway, is there a standard term for these things? If not, a better name
> than
> 'system process'?
>
>         Noel
>

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[COFF] Re: Terminology query - 'system process'?

[Dan Cross]

On Thu, Dec 14, 2023 at 5:17 PM Clem Cole <clemc@ccc.com> wrote:
> I don't know of a standard name.   We used to call the kernel processes or kernel threads also.

I've heard all combinations of (system|kernel) (thread|task|process),
all of which mean more or less the same thing: something the kernel
can schedule and run that doesn't have a userspace component, reusing
the basic concurrency primitives in the kernel for its own internal
purposes. I'm not sure I've heard "kernel daemon" before, but
intuitively I'd lump it into the same category unless I was told
otherwise (as Noel mentioned, of course Berkeley had the "pageout
daemon" which ran only in the kernel).

> For instance, in the original Masscomp EFS code, we had a handful of processes that got forked after the pager using kernel code.  Since the basic UNIX read/write from the user space scheme is synchronous, the premade pool of kernel processes was dispatched as needed when we listened for asynchronous remote requests for I/O. This is similar to the fact that asynchronous devices from serial or network interfaces need a pool of memory to stuff things into since you never know ahead of time when it will come.
> ᐧ

I remember reading a paper on the design of NFS (it may have been the
BSD paper) and there was a note about how the NFS server process ran
mostly in the kernel; user code created it, but pretty much all it did
was invoke a system call that implemented the server. That was kind of
neat.

        - Dan C.

> On Thu, Dec 14, 2023 at 4:48 PM Noel Chiappa <jnc@mercury.lcs.mit.edu> wrote:
>> So Lars Brinkhoff and I were chatting about daemons:
>>
>>   https://gunkies.org/wiki/Talk:Daemon
>>
>> and I pointed out that in addition to 'standard' daemons (e.g. the printer
>> spooler daemon, email daemon, etc, etc) there are some other things that are
>> daemon-like, but are fundamentally different in major ways (explained later
>> below). I dubbed them 'system processes', but I'm wondering if ayone knows if
>> there is a standard term for them? (Or, failing that, if they have a
>> suggestion for a better name?)
>>
>>
>> Early UNIX is one of the first systems to have one (process 0, the "scheduling (swapping)
>> process"), but the CACM "The UNIX Time-Sharing System" paper:
>>
>>   https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf
>>
>> doesn't even mention it, so no guidance there. Berkeley UNIX also has one,
>> mentioned in "Design and Implementation of the Berkeley Virtual Memory
>> Extensions to the UNIX Operating System":
>>
>>   http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf
>>
>> where it is called the "pageout daemon".("During system initialization, just
>> before the init process is created, the bootstrapping code creates process 2
>> which is known as the pageout daemon. It is this process that .. writ[es]
>> back modified pages. The process leaves its normal dormant state upon being
>> waken up due to the memory free list size dropping below an upper
>> threshold.") However, I think there are good reasons to dis-favour the term
>> 'daemon' for them.
>>
>>
>> For one thing, typical daemons look (to the kernel) just like 'normal'
>> processes: their object code is kept in a file, and is loaded into the
>> daemon's process when it starts, using the same mechanism that 'normal'
>> processes use for loading their code; daemons are often started long after
>> the kernel itself is started, and there is usually not a special mechanism in
>> the kernel to start daemons (on early UNIXes, /etc/rc is run by the 'init'
>> process, not the kernel); daemons interact with the kernel through system
>> calls, just like 'ordinary' processes; the daemon's process runs in 'user'
>> CPU mode (using the same standard memory mapping mechanisms, just like
>> blah-blah).
>>
>> 'System processes' do none of these things: their object code is linked into
>> the monolithic kernel, and is thus loaded by the bootstrap; the kernel
>> contains special provision for starting the system process, which start as
>> the kernel is starting; they don't do system calls, just call kernel routines
>> directly; they run in kernel mode, using the same memory mapping as the
>> kernel itself; etc, etc.
>>
>> Another important point is that system processes are highly intertwined with
>> the operation of the kernel; without the system process(es) operating
>> correctly, the operation of the system will quickly grind to a halt. The loss
>> of ordinary' daemons is usually not fatal; if the email daemon dies, the
>> system will keep running indefinitely. Not so, for the swapping process, or
>> the pageout daemon
>>
>>
>> Anyway, is there a standard term for these things? If not, a better name than
>> 'system process'?
>>
>>         Noel

[COFF] Re: Terminology query - 'system process'?

[Warner Losh]

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On Fri, Dec 15, 2023 at 7:21 AM Dan Cross <crossd@gmail.com> wrote:

> On Thu, Dec 14, 2023 at 5:17 PM Clem Cole <clemc@ccc.com> wrote:
> > I don't know of a standard name.   We used to call the kernel processes
> or kernel threads also.
>
> I've heard all combinations of (system|kernel) (thread|task|process),
> all of which mean more or less the same thing: something the kernel
> can schedule and run that doesn't have a userspace component, reusing
> the basic concurrency primitives in the kernel for its own internal
> purposes. I'm not sure I've heard "kernel daemon" before, but
> intuitively I'd lump it into the same category unless I was told
> otherwise (as Noel mentioned, of course Berkeley had the "pageout
> daemon" which ran only in the kernel).
>

FreeBSD (and likely others) have extended this to allow kernel
threads that we loosely call daemons as well. FreeBSD has APIs
for creating a kernel-only threads and processes...


> > For instance, in the original Masscomp EFS code, we had a handful of
> processes that got forked after the pager using kernel code.  Since the
> basic UNIX read/write from the user space scheme is synchronous, the
> premade pool of kernel processes was dispatched as needed when we listened
> for asynchronous remote requests for I/O. This is similar to the fact that
> asynchronous devices from serial or network interfaces need a pool of
> memory to stuff things into since you never know ahead of time when it will
> come.
> > ᐧ
>
> I remember reading a paper on the design of NFS (it may have been the
> BSD paper) and there was a note about how the NFS server process ran
> mostly in the kernel; user code created it, but pretty much all it did
> was invoke a system call that implemented the server. That was kind of
> neat.


I recall discussions with the kernel people at Solbourne who were bringing
up
SunOS 4.0 on Solbourne hardware about this. nfsd was little more than an N
way
fork followed by the system call. It provided a process context to sleep
in, which
couldn't be created in the kernel at the time. I've not gone to the
available SunOS
sources to confirm this is what's going on.

I'd thought, though, that this was the second nfsd implementation. The
first one
would decode the requests off the wire and schedule the I/O. It was only
when
there were issues with this approach that it moved into the kernel. This
was mostly
a context switch thing, but as more security measures were added to the
system
that root couldn't bypass, NFS needed to move into the kernel so it could
bypass
them. See getfh and similar system calls. I'm not sure how much of this was
done in SunOS, I'm only familiar with the post 4.4BSD work...

Warner


>         - Dan C.
>
> > On Thu, Dec 14, 2023 at 4:48 PM Noel Chiappa <jnc@mercury.lcs.mit.edu>
> wrote:
> >> So Lars Brinkhoff and I were chatting about daemons:
> >>
> >>   https://gunkies.org/wiki/Talk:Daemon
> >>
> >> and I pointed out that in addition to 'standard' daemons (e.g. the
> printer
> >> spooler daemon, email daemon, etc, etc) there are some other things
> that are
> >> daemon-like, but are fundamentally different in major ways (explained
> later
> >> below). I dubbed them 'system processes', but I'm wondering if ayone
> knows if
> >> there is a standard term for them? (Or, failing that, if they have a
> >> suggestion for a better name?)
> >>
> >>
> >> Early UNIX is one of the first systems to have one (process 0, the
> "scheduling (swapping)
> >> process"), but the CACM "The UNIX Time-Sharing System" paper:
> >>
> >>   https://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf
> >>
> >> doesn't even mention it, so no guidance there. Berkeley UNIX also has
> one,
> >> mentioned in "Design and Implementation of the Berkeley Virtual Memory
> >> Extensions to the UNIX Operating System":
> >>
> >>   http://roguelife.org/~fujita/COOKIES/HISTORY/3BSD/design.pdf
> >>
> >> where it is called the "pageout daemon".("During system initialization,
> just
> >> before the init process is created, the bootstrapping code creates
> process 2
> >> which is known as the pageout daemon. It is this process that ..
> writ[es]
> >> back modified pages. The process leaves its normal dormant state upon
> being
> >> waken up due to the memory free list size dropping below an upper
> >> threshold.") However, I think there are good reasons to dis-favour the
> term
> >> 'daemon' for them.
> >>
> >>
> >> For one thing, typical daemons look (to the kernel) just like 'normal'
> >> processes: their object code is kept in a file, and is loaded into the
> >> daemon's process when it starts, using the same mechanism that 'normal'
> >> processes use for loading their code; daemons are often started long
> after
> >> the kernel itself is started, and there is usually not a special
> mechanism in
> >> the kernel to start daemons (on early UNIXes, /etc/rc is run by the
> 'init'
> >> process, not the kernel); daemons interact with the kernel through
> system
> >> calls, just like 'ordinary' processes; the daemon's process runs in
> 'user'
> >> CPU mode (using the same standard memory mapping mechanisms, just like
> >> blah-blah).
> >>
> >> 'System processes' do none of these things: their object code is linked
> into
> >> the monolithic kernel, and is thus loaded by the bootstrap; the kernel
> >> contains special provision for starting the system process, which start
> as
> >> the kernel is starting; they don't do system calls, just call kernel
> routines
> >> directly; they run in kernel mode, using the same memory mapping as the
> >> kernel itself; etc, etc.
> >>
> >> Another important point is that system processes are highly intertwined
> with
> >> the operation of the kernel; without the system process(es) operating
> >> correctly, the operation of the system will quickly grind to a halt.
> The loss
> >> of ordinary' daemons is usually not fatal; if the email daemon dies, the
> >> system will keep running indefinitely. Not so, for the swapping
> process, or
> >> the pageout daemon
> >>
> >>
> >> Anyway, is there a standard term for these things? If not, a better
> name than
> >> 'system process'?
> >>
> >>         Noel
>

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[COFF] Re: Terminology query - 'system process'?

[Bakul Shah]

On Dec 15, 2023, at 6:21 AM, Dan Cross <crossd@gmail.com> wrote:
> 
> I remember reading a paper on the design of NFS (it may have been the
> BSD paper) and there was a note about how the NFS server process ran
> mostly in the kernel; user code created it, but pretty much all it did
> was invoke a system call that implemented the server. That was kind of
> neat.

At Valid Logic Systems I prototyped a relatively simple network filesystem.
Here there was no user code. There was one “agent” kernel thread per remote
system accessing local filesystem + a few more. The agent thread acted on
behalf of a remote system and maintained a session as long as at least one
local file/dir was referenced from that system. There were complications as it
was not a stateless design. I had to add code to detect when the remote
server/client died or rebooted and return ENXIO / clear out old state.

[COFF] Re: Terminology query - 'system process'?

[Lars Brinkhoff]

For the record, daring to stray outside Unix, ITS originally had a
"system job", and later split off a "core job".  Both running in monitor
mode.  Job means the same thing as process here, and monitor same as
kernel.

--- >8 --- cut and stop reading here --- >8 --- off topic --- >8 ---

In ITS terminology, "demon" means a (user space) process that is started
on demand by the system.  This could be due to an external event (say, a
network connection), or another process indicating a need for a service.
The demon may go away right after it has done its job, or linger around
for a while.

There's a separate term "dragon" which means a continuously running
background process.

[COFF] Re: Terminology query - 'system process'?

[Stuff Received]

On 2023-12-15 01:24, Lars Brinkhoff wrote:
> For the record, daring to stray outside Unix, ITS originally had a
> "system job", and later split off a "core job".  Both running in monitor
> mode.  Job means the same thing as process here, and monitor same as
> kernel.
> 
> --- >8 --- cut and stop reading here --- >8 --- off topic --- >8 ---

 From https://www.tuhs.org/cgi-bin/mailman/listinfo/coff

"The Computer Old Farts Forum provides a place for people to discuss the 
history of computers and their future."

It seems that you are well within bounds.

S.