In 2014, systemd started choosing fq_codel as the default_qdisc in order to fight internet bufferbloat.
e6c253e363fa98c99ea7
While the subsequent change made this change no longer trigger warnings if fq_codel wasn't present, it is still recommended to have this enabled. Add the necessary kernel configuration to the documentation.
We already use __VA_OPT__ in multiple places, which was introduced in
gcc 8 [0], so let's bump the baseline to reflect that. I chose gcc 8.4,
as that was the lowest 8.x version I could easily get my hands on when I
verified this (on Ubuntu Focal with the gcc-8 package).
Closes: #31191
[0] https://gcc.gnu.org/gcc-8/changes.html
Let's replace the "compat" module in our proposed nsswitch.conf
configuration with "files", since it is not 1995 anymore.
Fedora and other distros have deprecated and removed NIS support a while
back. While others still retain some support I am not sure we should
advertise it in our examples. Downstream can of course still use
"compat" instead of "files" if they want to, but let's not confuse
people who don't care about NIS anymore with this.
Also, bring the nsswitch.conf snippet in README in line with what our
man pages say.
Also see: https://fedoraproject.org/wiki/Changes/retire_NIS_user_space_utils
static versions of libsystems.so are not really supportable, and
encourages mix&match which we cannot really support. Make the wording
about this stronger in the README, since people apparently don'd read to
the last paragraph.
libpython was added in 2cc86f094a, it seems
because of python-systemd module that we built. But libpython by itself
is not enough for actual python programs, and now we also list python itself,
so let's drop libpython from the list.
meson requires >= 3.7. We have CI that runs on CentOS8 with Python 3.6, but
let's not provide official support for an EOL Python version. Individual
distributions can provide backports, but we don't need to mention that in
the user-facing docs. According to [1], 3.7 is on life support and 3.6 is EOL.
[1] https://devguide.python.org/versions/
This adds back sd-boot builds by using meson compile targets directly.
We can do this now, because userspace binaries use the special
dependency that allows us to easily separate flags, so that we don't
pass anything to EFI builds that shouldn't be passed.
Additionally, we pass a bunch of flags to hopefully disable/override any
distro provided flags that should not be used for EFI binaries.
Fixes: #12275
This drops all mentions of gnu-efi and its manual build machinery. A
future commit will bring bootloader builds back. A new bootloader meson
option is now used to control whether to build sd-boot and its userspace
tooling.
Most of the support for valgrind was under HAVE_VALGRIND_VALGRIND_H, i.e. we
would enable if the valgrind headers were found. The operations then we be
conditionalized on RUNNING_UNDER_VALGRIND.
But in a few places we had code which was conditionalized on VALGRIND, i.e. the
config option. I noticed because I compiled with -Dvalgrind=true on a machine
that didn't have valgrind.h, and the build failed because
RUNNING_UNDER_VALGRIND was not defined. My first idea was to add a check that
the header is present if the option is set, but it seems better to just remove
the option. The code to support valgrind is trivial, and if we're
!RUNNING_UNDER_VALGRIND, it has negligible cost. And the case of running under
valgrind is always some special testing/debugging mode, so we should just do
those extra steps to make valgrind output cleaner. Removing the option makes
things simpler and we don't have to think if something should be covered by the
one or the other configuration bit.
I had a vague recollection that in some places we used -Dvalgrind=true not
for valgrind support, but to enable additional cleanup under other sanitizers.
But that code would fail to build without the valgrind headers anyway, so
I'm not sure if that was still used. If there are uses like that, we can
extend the condition for cleanup_pools().
We already depend on the skeleton APIs introduced in libbpf 0.7 so
let's bump our minimum version to reflect that.
We don't enforce bpf compilation on mkosi anymore since not all
distros have sufficiently up-to-date libbpf available.
We had a description in README, and an outdated list in the man page.
I think we should keep a reference-style list in the man page. The description
in README is more free-form.
* Avoid traling slash as most links are defined without.
* Always use https:// protocol and www. subdomain
Allows for easier tree-wide linkvalidation
for our migration to systemd.io.
git archive automatically uses gzip when --output=*.tar.gz is used, but
not for other extensions. Thus we need to invoke the compressor separately :(
It's a good pattern to use a variable for the repeating number, so let's
recommend that.
With meson-0.60, meson compile stopped working with some targets:
$ meson compile -C build update-man-rules
ERROR: Can't invoke target `update-man-rules`: ambiguous name. Add target type and/or path: `PATH/NAME:TYPE`
This is obviously a regression in meson, but based on a chat with the
maintainers, it seems that there's some disagreement as to whether 'meson
compile' is useful and how exactly it should work. Since we're already at
meson 0.60.3 and this hasn't been fixed, and people generally don't seem to
consider this an issue, let's return to documenting the usual practice of
'ninja -C build' that just works everywhere.
(Since nobody has raised any fuss in systemd, it means that people are
generally using the shorter form during development too. I only noticed
because I pasted a command from the release docs when preparing -rc1.)
After various long discussions
(https://lists.freedesktop.org/archives/systemd-devel/2022-March/047587.html,
https://lwn.net/Articles/889610/), there is no clear answer what the minimum
version should be. Bumping the version above 3.15 doesn't allow us to make any
significant simplifications (unless we went *much* higher). In particular, even
renameat2() is not fully supported with latest kernel versions, e.g. nfs still
doesn't have it. And the bpf stuff is optional anyway. So let's just say that
4.15 is what we recommend, because it provides fairly complete cgroups-v2, but
without any removals of compat in the code.
Let's raise our supported baseline a bit: CLOCK_BOOTTIME started to work
with timerfd in kernel 3.15 (i.e. back in 2014), let's require support
for it now.
This will raise our baseline only modestly from 3.13 → 3.15.
