Re: Back-patch use of unnamed POSIX semaphores for Linux?

On Wed, Dec 7, 2016 at 6:49 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Alvaro Herrera <alvherre@2ndquadrant.com> writes:
>> Tom Lane wrote:
>>> Color me confused ... maybe systemd's behavior has changed?
>
>> https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/ZNQW72UP36UAFMX53HPFFQTWTQDZVJ3M/
>
> I see Lennart hasn't gotten any less convinced that he's always right
> since I left Red Hat :-(

This thread does seem to give that impression.  It's nice to know
there are engineers in the world even more arrogant than we are.  :-)

> But anyway, it's a demonstrable fact that Fedora 25 has KillUserProcesses
> off by default, even though it contains systemd-231.  I assume FESCO
> brought down the hammer at some point.

https://pagure.io/fesco/issue/1600 seems to suggest that it's merely
in abeyance.  (See the first two updates and the last one for the
executive summary.)

> This still doesn't address the real question, which is whether RemoveIPC
> does anything if KillUserProcesses is off, and whether that behavior
> has changed.  I don't see anything about RemoveIPC in that thread.

http://www.dsm.fordham.edu/cgi-bin/man-cgi.pl?topic=logind.conf&ampsect=5
suggests that KillUserProcesses and RemoveIPC are separate cleanup
behaviors triggered by the same underlying cause (termination of last
session).

-- 
Robert Haas
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