Re: OpenBSD 7.3 found a process with PID 0

Il 26/09/23 17:30, Claudio Jeker ha scritto:
> On Tue, Sep 26, 2023 at 05:13:46PM +0200, Andreas Kähäri wrote:
>> On Tue, Sep 26, 2023 at 04:59:22PM +0200, Alessandro Baggi wrote:
>>> Hi list,
>>> running this python3 script:
>>>
>>> #!/usr/bin/env python3
>>> import psutil
>>>
>>> pids = psutil.pids()
>>> for i in pids:
>>> p = psutil.Process(i)
>>> with p.oneshot():
>>> print(str(i) + " " + p.name())
>>>
>>> The result start with:
>>>
>>> 0 swapper
>>> 1 init
>>> 536 smtpd
>>> 868 ksh
>>> ...
>>>
>>> This process does not appear in ps, top and htop.
>>
>> $ ps -p 0
>> PID TT STAT TIME COMMAND
>> 0 ?? DK 0:02.19 (swapper)
>>
>> For top, you need to press S to show system processes. I don't use
>> htop, but I assume it has a similar capability to show system processes.
>>
>>>
>>> How could be that there is a process with PID 0 before init?
>>> Probably I'm missing something about OpenBSD core.
>>>
>>> Can someone point me in the right direction?
>>>
>>
>> See uvm_init(9):
>>
>> The swapper process swaps in runnable processes that are
>> currently swapped out, if there is room.
>>
>
> ... and this is a lie. The swapper process does nothing.
>

Ok, but why it is running?