This hooks the cgroup support up to the config system so it can actually
be used.
To make use of this in unit a new "cgroup" section has been added to the
isolation configuration.
e.g
"applications": {
"python": {
"type": "python",
"processes": 5,
"path": "/opt/unit/unit-cgroup-test/",
"module": "app",
"isolation": {
"cgroup": {
"path": "app/python"
}
}
}
}
Now there are two ways to specify the path, relative, like the above
(without a leading '/') and absolute (with a leading '/').
In the above case the "python" application is placed into its own cgroup
under CGROUP_ROOT/<main unit process cgroup>/app/python. Whereas if you
specified say
"path": "/unit/app/python"
Then the python application would be placed under
CGROUP_ROOT/unit/app/python
The first option allows you to easily take advantage of any resource
limits that have already been configured for unit.
With the second method (absolute pathname) if you know of an already
existing cgroup where you'd like to place it, you can, e.g
"path": "/system.slice/unit/python"
Where system.slice has already been created by systemd and may already
have some overall system limits applied which would also apply to unit.
Limits apply down the hierarchy and lower groups can't exceed the
previous group limits.
So what does this actually look like? Lets take the unit-calculator
application[0] and have each of its applications placed into their own
cgroup. If we give each application a new section like
"isolation": {
"cgroup": {
"path": "/unit/unit-calculator/add"
}
}
changing the path for each one, we can visualise the result with the
systemd-cgls command, e.g
│ └─session-5.scope (#4561)
│ ├─ 6667 sshd: andrew [priv]
│ ├─ 6684 sshd: andrew@pts/0
│ ├─ 6685 -bash
│ ├─ 12632 unit: main v1.28.0 [/opt/unit/sbin/unitd --control 127.0.0.1:808>
│ ├─ 12634 unit: controller
│ ├─ 12635 unit: router
│ ├─ 13550 systemd-cgls
│ └─ 13551 less
├─unit (#4759)
│ └─unit-calculator (#5037)
│ ├─subtract (#5069)
│ │ ├─ 12650 unit: "subtract" prototype
│ │ └─ 12651 unit: "subtract" application
│ ├─multiply (#5085)
│ │ ├─ 12653 unit: "multiply" prototype
│ │ └─ 12654 unit: "multiply" application
│ ├─divide (#5101)
│ │ ├─ 12671 unit: "divide" prototype
│ │ └─ 12672 node divide.js
│ ├─sqroot (#5117)
│ │ ├─ 12679 unit: "sqroot" prototype
│ │ └─ 12680 /home/andrew/src/unit-calculator/sqroot/sqroot
│ └─add (#5053)
│ ├─ 12648 unit: "add" prototype
│ └─ 12649 unit: "add" application
We used an absolute path so the cgroups will be created relative to the
main cgroupfs mount, e.g /sys/fs/cgroup
We can see that the main unit processes are in the same cgroup as the
shell from where they were started, by default child process are placed
into the same cgroup as the parent.
Then we can see that each application has been placed into its own
cgroup under /sys/fs/cgroup
Taking another example of a simple 5 process python application, with
"isolation": {
"cgroup": {
"path": "app/python"
}
}
Here we have specified a relative path and thus the python application
will be placed below the existing cgroup that contains the main unit
process. E.g
│ │ │ ├─app-glib-cinnamon\x2dcustom\x2dlauncher\x2d3-43951.scope (#90951)
│ │ │ │ ├─ 988 unit: main v1.28.0 [/opt/unit/sbin/unitd --no-daemon]
│ │ │ │ ├─ 990 unit: controller
│ │ │ │ ├─ 991 unit: router
│ │ │ │ ├─ 43951 xterm -bg rgb:20/20/20 -fg white -fa DejaVu Sans Mono
│ │ │ │ ├─ 43956 bash
│ │ │ │ ├─ 58828 sudo -i
│ │ │ │ ├─ 58831 -bash
│ │ │ │ └─app (#107351)
│ │ │ │ └─python (#107367)
│ │ │ │ ├─ 992 unit: "python" prototype
│ │ │ │ ├─ 993 unit: "python" application
│ │ │ │ ├─ 994 unit: "python" application
│ │ │ │ ├─ 995 unit: "python" application
│ │ │ │ ├─ 996 unit: "python" application
│ │ │ │ └─ 997 unit: "python" application
[0]: <https://github.com/lcrilly/unit-calculator>
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
This commit enables the building of the cgroup code. This is only built
when the cgroupv2 filesystem is found.
If cgroupv2 support is found then
cgroupv2: .................. YES
will be printed by ./configure
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
This commit hooks into the cgroup infrastructure added in the previous
commit to create per-application cgroups.
It does this by adding each "prototype process" into its own cgroup,
then each child process inherits its parents cgroup.
If we fail to create a cgroup we simply fail the process. This behaviour
may get enhanced in the future.
This won't actually do anything yet. Subsequent commits will hook this
up to the build and config systems.
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Firstly, this is not to be confused with CLONE_NEWCGROUP which unit
already supports and is related to namespaces. To re-cap, namespaces
allow processes to have different views of various parts of the system
such as filesystem mounts, networking, hostname etc.
Whereas cgroup[0] is a Linux kernel facility for collecting a bunch of
processes together to perform some task on the group as a whole, for
example to implement resource limits.
There are two parts to cgroup, the core part of organising processes
into a hierarchy and the controllers which are responsible for enforcing
resource limits etc.
There are currently two versions of the cgroup sub-system, the original
cgroup and a version 2[1] introduced in 3.16 (August 2014) and marked
stable in 4.5 (March 2016).
This commit supports the cgroup V2 API and implements the ability to
place applications into their own cgroup on a per-application basis.
You can put them each into their own cgroup or you can group some
together. The ability to set resource limits can easily be added in
future.
The initial use case of this would be to aid in observability of unit
applications which becomes much easier if you can just monitor them on a
per cgroup basis.
One thing to note about cgroup, is that unlike namespaces which are
controlled via system calls such as clone(2) and unshare(2), cgroups are
setup and controlled through the cgroupfs pseudo-filesystem.
cgroup is Linux only and this support will only be enabled if configure
finds the cgroup2 filesystem mount, e.g
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,seclabel,nsdelegate,memory_recursiveprot)
The cgroups are removed on shutdown or as required on reconfiguration.
This commit just adds the basic infrastructure for using cgroups within
unit. Subsequent commits will wire up this support.
It supports creating cgroups relative to the main cgroup root and also
below the cgroup of the main unit process.
[0]: <https://man7.org/linux/man-pages/man7/cgroups.7.html>
[1]: <https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.html>
Cc: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Add simple wrapper functions for fopen(3) and fclose(3) that are
somewhat akin to the nxt_file_open() and nxt_file_close() wrappers that
log errors.
Suggested-by: Alejandro Colomar <alx@nginx.com>
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Andrei reported an issue with building unit when using '-O0' with GCC
producing the following compiler errors
cc -c -pipe -fPIC -fvisibility=hidden -O -W -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wmissing-prototypes -Werror -g -O0 -I src -I build \
\
\
-o build/src/nxt_unit.o \
-MMD -MF build/src/nxt_unit.dep -MT build/src/nxt_unit.o \
src/nxt_unit.c
src/nxt_unit.c: In function ‘nxt_unit_log’:
src/nxt_unit.c:6601:9: error: ‘msg’ may be used uninitialized [-Werror=maybe-uninitialized]
6601 | p = nxt_unit_snprint_prefix(p, end, pid, level);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/nxt_unit.c:6682:1: note: by argument 2 of type ‘const char *’ to ‘nxt_unit_snprint_prefix’ declared here
6682 | nxt_unit_snprint_prefix(char *p, const char *end, pid_t pid, int level)
| ^~~~~~~~~~~~~~~~~~~~~~~
src/nxt_unit.c:6582:22: note: ‘msg’ declared here
6582 | char msg[NXT_MAX_ERROR_STR], *p, *end;
| ^~~
src/nxt_unit.c: In function ‘nxt_unit_req_log’:
src/nxt_unit.c:6645:9: error: ‘msg’ may be used uninitialized [-Werror=maybe-uninitialized]
6645 | p = nxt_unit_snprint_prefix(p, end, pid, level);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/nxt_unit.c:6682:1: note: by argument 2 of type ‘const char *’ to ‘nxt_unit_snprint_prefix’ declared here
6682 | nxt_unit_snprint_prefix(char *p, const char *end, pid_t pid, int level)
| ^~~~~~~~~~~~~~~~~~~~~~~
src/nxt_unit.c:6625:35: note: ‘msg’ declared here
6625 | char msg[NXT_MAX_ERROR_STR], *p, *end;
| ^~~
cc1: all warnings being treated as errors
The above was reproduced with
$ ./configure --cc-opt=-O0 && ./configure python && make -j4
This warning doesn't happen on clang (15.0.4) or GCC (8.3) and seems to
have been introduced in GCC 11. The above is from GCC (12.2.1, Fedora
37).
The trigger of this GCC issue is actually part of a commit I introduced
a few months back to constify some function parameters and it seems the
consensus for how to resolve this problem is to simply remove the const
qualifier from the *end parameter to nxt_unit_snprint_prefix().
Reported-by: Andrei Zeliankou <zelenkov@nginx.com>
Link: <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100417>
Link: <https://github.com/samtools/htslib/pull/1285>
Link: <https://gcc.gnu.org/gcc-11/changes.html>
Fixes: 4418f99 ("Constified numerous function parameters.")
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Python 3.8 added a new Python initialisation configuration API[0].
Python 3.11 marked the old API as deprecated resulting in the following
compiler warnings which we treat as errors, failing the build
src/python/nxt_python.c: In function ‘nxt_python_start’:
src/python/nxt_python.c:130:13: error: ‘Py_SetProgramName’ is deprecated [-Werror=deprecated-declarations]
130 | Py_SetProgramName(nxt_py_home);
| ^~~~~~~~~~~~~~~~~
In file included from /opt/python-3.11/include/python3.11/Python.h:94,
from src/python/nxt_python.c:7:
/opt/python-3.11/include/python3.11/pylifecycle.h:37:38: note: declared here
37 | Py_DEPRECATED(3.11) PyAPI_FUNC(void) Py_SetProgramName(const wchar_t *);
| ^~~~~~~~~~~~~~~~~
src/python/nxt_python.c:134:13: error: ‘Py_SetPythonHome’ is deprecated [-Werror=deprecated-declarations]
134 | Py_SetPythonHome(nxt_py_home);
| ^~~~~~~~~~~~~~~~
/opt/python-3.11/include/python3.11/pylifecycle.h:40:38: note: declared here
40 | Py_DEPRECATED(3.11) PyAPI_FUNC(void) Py_SetPythonHome(const wchar_t *);
| ^~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
We actually have a few config scenarios: Python < 3, Python >= 3.0 < 3.8
and for Python 3 we have two configs where we select one based on
virtual environment setup.
Factor out the Python 3 config initialisation into its own function. We
actually create two functions, one for Python 3.8+ and one for older
Python 3. We pick the right function to use at build time.
The new API also has error checking (where the old API doesn't) which we
handle.
[0]: https://peps.python.org/pep-0587/
Closes: <https://github.com/nginx/unit/issues/710>
[ Andrew: Expanded upon patch from @sandeep-gh ]
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Both @lucatacconi & @mwoodpatrick reported what appears to be the same
issue on GitHub. Namely that when using the PHP language module and
trying to access a URL that is a directory but without specifying the
trailing '/', they were getting a '503 Service Unavailable' error.
Note: This is when _not_ using the 'script' option.
E.g with the following config
{
"listeners": {
"[::1]:8080": {
"pass": "applications/php"
}
},
"applications": {
"php": {
"type": "php",
"root": "/var/tmp/unit-php"
}
}
}
and with a directory path of /var/tmp/unit-php/foo containing an
index.php, you would see the following
$ curl http://localhost/foo
<title>Error 503</title>
Error 503
However
$ curl http://localhost/foo/
would work and serve up the index.php
This commit fixes the above so you get the desired behaviour without
specifying the trailing '/' by doing the following
1] If the URL doesn't end in .php and doesn't have a trailing '/'
then check if the requested path is a directory.
2) If it is a directory then create a 301 re-direct pointing to it.
This matches the behaviour of the likes of nginx, Apache and
lighttpd.
This also matches the behaviour of the "share" action in Unit.
This doesn't effect the behaviour of the 'script' option which bypasses
the nxt_php_dynamic_request() function.
This also adds a couple of tests to test/test_php_application.py to
ensure this continues to work.
Closes: <https://github.com/nginx/unit/issues/717>
Closes: <https://github.com/nginx/unit/issues/753>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Future releases of GCC will render function definitions like
func()
invalid by default. See the previous commit 09f88c9 ("Fixed main()
prototypes in auto tests.") for details.
Such functions should be defined like
func(void)
This is a good thing to do regardless of the upcoming GCC changes.
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Future releases of GCC are planning to remove[0] default support for
some old features that were removed from C99 but GCC still accepts.
We can test for these changes by using the following -Werror=
directives
-Werror=implicit-int
-Werror=implicit-function-declaration
-Werror=int-conversion
-Werror=strict-prototypes
-Werror=old-style-definition
Doing so revealed an issue with the auto/ tests in that the test
programs always define main as
int main()
rather than
int main(void)
which results in a bunch of errors like
build/autotest.c:3:23: error: function declaration isn't a prototype [-Werror=strict-prototypes]
3 | int main() {
| ^~~~
build/autotest.c: In function 'main':
build/autotest.c:3:23: error: old-style function definition [-Werror=old-style-definition]
The fix was easy, it only required fixing the main prototype with
find -type f -exec sed -i 's/int main() {/int main(void) {/g' {} \;
Regardless of these upcoming GCC changes, this is probably a good thing
to do anyway for correctness.
[0]: https://fedoraproject.org/wiki/Changes/PortingToModernC
Link: <https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/CJXKTLXJUPZ4F2C2VQOTNMEA5JAUPMBD/>
Link: <https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/6SGHPHPAXKCVJ6PUZ57WVDQ5TDBVIRMF/>
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
@alejandro-colomar reported that the build was broken on MacOS
cc -o build/unitd -pipe -fPIC -fvisibility=hidden -O -W -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -fstrict-aliasing -Wstrict-overflow=5 -Wmissing-prototypes -Werror -g \
build/src/nxt_main.o build/libnxt.a \
\
\
-L/usr/local/Cellar/pcre2/10.40/lib -lpcre2-8
Undefined symbols for architecture x86_64:
"_nxt_fs_mkdir_parent", referenced from:
_nxt_runtime_pid_file_create in libnxt.a(nxt_runtime.o)
_nxt_runtime_controller_socket in libnxt.a(nxt_controller.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [build/unitd] Error 1
This was due to commit 57fc920 ("Socket: Created control socket & pid file
directories.").
This happened because this commit introduced the usage of
nxt_fs_mkdir_parent() in core code which uses nxt_fs_mkdir(), both of
these are defined in src/nxt_fs.c. It turns out however that this file
doesn't get built on MacOS (or any system that isn't Linux or that
lacks a FreeBSD compatible nmount(2) system call) due to the following
In auto/sources we have
if [ $NXT_HAVE_ROOTFS = YES ]; then
NXT_LIB_SRCS="$NXT_LIB_SRCS src/nxt_fs.c"
fi
NXT_HAVE_ROOTFS is set in auto/isolation
If [ $NXT_HAVE_MOUNT = YES -a $NXT_HAVE_UNMOUNT = YES ]; then
NXT_HAVE_ROOTFS=YES
cat << END >> $NXT_AUTO_CONFIG_H
#ifndef NXT_HAVE_ISOLATION_ROOTFS
#define NXT_HAVE_ISOLATION_ROOTFS 1
#endif
END
fi
While we do have a check for a generic umount(2) which is found on
MacOS, for mount(2) we currently only check for the Linux mount(2) and
FreeBSD nmount(2) system calls. So NXT_HAVE_ROOTFS is set to NO on MacOS
and we don't build src/nxt_fs.c
This fixes the immediate build issue by taking the mount/umount OS
support out of nxt_fs.c into a new nxt_fs_mount.c file which is guarded
by the above while we now build nxt_fs.c unconditionally.
This should fix the build on any _supported_ system.
Reported-by: Alejandro Colomar <alx@nginx.com>
Fixes: 57fc920 ("Socket: Created control socket & pid file directories.")
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
This is a preparatory patch that renames the 'local' and 'local_length'
members of the nxt_unit_request_t structure to 'local_addr' and
'local_addr_length' in preparation for the adding of 'local_port' and
'local_port_length' members.
Suggested-by: Zhidao HONG <z.hong@f5.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
@alejandro-colomar reported an issue on GitHub whereby Unit would fail
to start due to not being able to create the control socket (a Unix
Domain Socket)
2022/08/05 20:12:22 [alert] 21613#21613 bind(6,
unix:/opt/local/unit/var/run/unit/control.unit.sock.tmp)
failed (2: No such file or directory)
This could happen if the control socket was set to a directory that
doesn't exist. A common place to put the control socket would be under
/run/unit, and while /run will exist, /run/unit may well not (/run
is/should be cleared on each boot).
The pid file would also generally go under /run/unit, though this is
created after the control socket, however it could go someplace else so
we should also ensure its directory exists.
This commit will try to create the pid file and control sockets parent
directory. In some cases the user will need to ensure that the rest of
the path already exists.
This adds a new nxt_fs_mkdir_parent() function that given a full path
to a file (or directory), strips the last component off before passing
the remaining directory path to nxt_fs_mkdir().
Cc: Konstantin Pavlov <thresh@nginx.com>
Closes: <https://github.com/nginx/unit/issues/742>
Reported-by: Alejandro Colomar <alx@nginx.com>
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Tested-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
This file is used by git (maybe also hg) to map different identities.
It can be used to map different names/email addresses to a preferred
name/email. So if you have authored/committed under different
names/email addresses you can map all these to a particular name/email.
Certain git commands (log, shortlog, show, blame etc) will consult this
file and show the Author/Committer accordingly.
Note: This does _not_ change history, this is simply used by various
commands to alter their output and can be disabled for some commands
with the --no-mailmap option.
This can be useful for commands like git shortlog so that all your
commits are shown under a single identity and also so people have an
up to date email address should they wish to contact you. And just for
overall consistency.
Seeing as I've already committed under two different email addresses
(not counting this one), I've put entries in this file to map my email
addresses to my @nginx.com one.
See also, gitmailmap(5).
Acked-by: Alex Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>
Andrew Clayton