Re: WARNING: Low file descriptor limit: 4096

2026-03-10 Thread Marcin Juszkiewicz

W dniu 10.03.2026 o 01:37, Oron Peled pisze:

 > on my gnome system this also works correctly.


On my Fedora-43 laptop with KDE plasma 6.6 (everything fully up-to-date):

$ ulimit -n -S; ulimit -n -H

1024

524288


Checked this on another Fedora-43 server I have (without any desktop) -- 
same results.



I.e: probably it's being set somewhere else -- e.g: some global/personal 
shell scripts (/etc/profile.d/*.sh, ~/.bashrc, whatever)


Yes. I checked my whole setup and turned out that one of tools run from 
~/.bashrc messed setup.


All works now.

--
___
devel mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Fedora Code of Conduct: 
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: 
https://lists.fedoraproject.org/archives/list/[email protected]
Do not reply to spam, report it: 
https://forge.fedoraproject.org/infra/tickets/issues/new


Re: WARNING: Low file descriptor limit: 4096

2026-03-09 Thread Oron Peled
On Monday, 2 March 2026 12:29:05 IST Lennart Poettering wrote:
> On Mo, 02.03.26 11:20, Marcin Juszkiewicz ([email protected]) wrote:
> 
> > What is a proper, expected, amount of file descriptors available to the
> > user of Fedora Linux 43?
> >
> > When Steam gets installed two new files are added to the systemd
> > configuration:
> >
> > /usr/lib/systemd/user.conf.d/01-steam.conf
> > /usr/lib/systemd/system.conf.d/01-steam.conf
> >
> >
> > Both bump amount of file descriptors to 1024:1048576 (lower:upper limit):
> >
> > [Manager]
> > DefaultLimitNOFILE=1024:1048576
> 
> Note that systemd's defaults nowadays are 1024:524288, which overrides
> the kernel defaults of 1024:4096.
> 
> > And asking systemd confirms that:
> >
> > $ systemd-analyze cat-config systemd/user.conf|grep NOFILE
> > DefaultLimitNOFILE=1024:1048576
> >
> > $ systemd-analyze cat-config systemd/system.conf|grep NOFILE
> > DefaultLimitNOFILE=1024:1048576
> >
> > So same values should appear when "ulimit -n" is called, right?
> >
> > Terminal (Konsole, XTerm) started in KDE session says otherwise:
> >
> > $ ulimit -n -S; ulimit -n -H
> > 4096
> > 4096
> 
> Uh, this is a bug. the soft limit should not be set to 4096 in generic
> code, because that can break select(). programs should bump their soft
> limit only if their know they are never going to use select(), but
> only more modern polling mechs, such as poll(), epoll, iouring. And
> they should reset the softlimit to 1K whenever forking things off, to
> not break client.s
> 
> to me this smells like a bug in kde. it should neither lower the hard
> limit to 4K, nor raise the soft limit to 4K...
> 
> on my gnome system this also works correctly.

On my Fedora-43 laptop with KDE plasma 6.6 (everything fully up-to-date):
$ ulimit -n -S; ulimit -n -H
1024
524288

Checked this on another Fedora-43 server I have (without any desktop) -- same 
results.

I.e: probably it's being set somewhere else -- e.g: some global/personal shell 
scripts (/etc/profile.d/*.sh, ~/.bashrc, whatever)

-- 
Oron Peled Voice: +972-4-8228492

"Man cannot discover new oceans unless he has the courage to lose sight of
the shore..."

-- 
___
devel mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Fedora Code of Conduct: 
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: 
https://lists.fedoraproject.org/archives/list/[email protected]
Do not reply to spam, report it: 
https://forge.fedoraproject.org/infra/tickets/issues/new


Re: WARNING: Low file descriptor limit: 4096

2026-03-02 Thread Lennart Poettering
On Mo, 02.03.26 11:20, Marcin Juszkiewicz ([email protected]) wrote:

> What is a proper, expected, amount of file descriptors available to the
> user of Fedora Linux 43?
>
> When Steam gets installed two new files are added to the systemd
> configuration:
>
> /usr/lib/systemd/user.conf.d/01-steam.conf
> /usr/lib/systemd/system.conf.d/01-steam.conf
>
>
> Both bump amount of file descriptors to 1024:1048576 (lower:upper limit):
>
> [Manager]
> DefaultLimitNOFILE=1024:1048576

Note that systemd's defaults nowadays are 1024:524288, which overrides
the kernel defaults of 1024:4096.

> And asking systemd confirms that:
>
> $ systemd-analyze cat-config systemd/user.conf|grep NOFILE
> DefaultLimitNOFILE=1024:1048576
>
> $ systemd-analyze cat-config systemd/system.conf|grep NOFILE
> DefaultLimitNOFILE=1024:1048576
>
> So same values should appear when "ulimit -n" is called, right?
>
> Terminal (Konsole, XTerm) started in KDE session says otherwise:
>
> $ ulimit -n -S; ulimit -n -H
> 4096
> 4096

Uh, this is a bug. the soft limit should not be set to 4096 in generic
code, because that can break select(). programs should bump their soft
limit only if their know they are never going to use select(), but
only more modern polling mechs, such as poll(), epoll, iouring. And
they should reset the softlimit to 1K whenever forking things off, to
not break client.s

to me this smells like a bug in kde. it should neither lower the hard
limit to 4K, nor raise the soft limit to 4K...

on my gnome system this also works correctly.

Lennart

--
Lennart Poettering, Berlin
-- 
___
devel mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Fedora Code of Conduct: 
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: 
https://lists.fedoraproject.org/archives/list/[email protected]
Do not reply to spam, report it: 
https://forge.fedoraproject.org/infra/tickets/issues/new