systemd-analyze — Analyze system boot-up performance
systemd-analyze [OPTIONS...] [time]
systemd-analyze [OPTIONS...] blame
systemd-analyze [OPTIONS...] critical-chain [UNIT...]
systemd-analyze [OPTIONS...] plot [> file.svg]
systemd-analyze [OPTIONS...] dot [PATTERN...] [> file.dot]
systemd-analyze [OPTIONS...] dump
systemd-analyze [OPTIONS...] set-log-level [LEVEL]
systemd-analyze [OPTIONS...] verify [FILES...]
systemd-analyze may be used to determine system boot-up performance statistics and retrieve other state and tracing information from the system and service manager, and to verify the correctness of unit files.
systemd-analyze time prints the time spent in the kernel before userspace has been reached, the time spent in the initial RAM disk (initrd) before normal system userspace has been reached, and the time normal system userspace took to initialize. Note that these measurements simply measure the time passed up to the point where all system services have been spawned, but not necessarily until they fully finished initialization or the disk is idle.
systemd-analyze blame prints a list of all running units, ordered by the time they took to initialize. This information may be used to optimize boot-up times. Note that the output might be misleading as the initialization of one service might be slow simply because it waits for the initialization of another service to complete.
systemd-analyze critical-chain
[UNIT...] prints a tree of
the time-critical chain of units (for each of the specified
UNITs or for the default target
otherwise). The time after the unit is active or started is
printed after the "@" character. The time the unit takes to start
is printed after the "+" character. Note that the output might be
misleading as the initialization of one service might depend on
socket activation and because of the parallel execution of
units.
systemd-analyze plot prints an SVG graphic detailing which system services have been started at what time, highlighting the time they spent on initialization.
systemd-analyze dot generates textual
dependency graph description in dot format for further processing
with the GraphViz
dot(1)
tool. Use a command line like systemd-analyze dot | dot
-Tsvg > systemd.svg to generate a graphical dependency
tree. Unless --order or
--require is passed, the generated graph will
show both ordering and requirement dependencies. Optional pattern
globbing style specifications (e.g. *.target)
may be given at the end. A unit dependency is included in the
graph if any of these patterns match either the origin or
destination node.
systemd-analyze dump outputs a (usually very long) human-readable serialization of the complete server state. Its format is subject to change without notice and should not be parsed by applications.
systemd-analyze set-log-level
LEVEL changes the current log
level of the systemd daemon to
LEVEL (accepts the same values as
--log-level= described in
systemd(1)).
systemd-analyze verify will load unit files and print warnings if any errors are detected. Files specified on the command line will be loaded, but also any other units referenced by them. This command works by prepending the directories for all command line arguments at the beginning of the unit load path, which means that all units files found in those directories will be used in preference to the unit files found in the standard locations, even if not listed explicitly.
If no command is passed, systemd-analyze time is implied.
The following options are understood:
--user¶Operates on the user systemd instance.
--system¶Operates on the system systemd instance. This is the implied default.
--order, --require¶When used in conjunction with the
dot command (see above), selects which
dependencies are shown in the dependency graph. If
--order is passed, only dependencies of type
After= or Before= are
shown. If --require is passed, only
dependencies of type Requires=,
RequiresOverridable=,
Requisite=,
RequisiteOverridable=,
Wants= and Conflicts=
are shown. If neither is passed, this shows dependencies of
all these types.
--from-pattern=, --to-pattern=¶When used in conjunction with the dot command (see above), this selects which relationships are shown in the dependency graph. Both options require a glob(7) pattern as an argument, which will be matched against the left-hand and the right-hand, respectively, nodes of a relationship.
Each of these can be used more than once, in which case the unit name must match one of the values. When tests for both sides of the relation are present, a relation must pass both tests to be shown. When patterns are also specified as positional arguments, they must match at least one side of the relation. In other words, patterns specified with those two options will trim the list of edges matched by the positional arguments, if any are given, and fully determine the list of edges shown otherwise.
--fuzz=timespan¶When used in conjunction with the
critical-chain command (see above), also
show units, which finished timespan
earlier, than the latest unit in the same level. The unit of
timespan is seconds unless
specified with a different unit, e.g.
"50ms".
--no-man¶Do not invoke man to verify the existence of
man pages listed in Documentation=.
-H, --host=¶Execute the operation remotely. Specify a hostname, or a
username and hostname separated by "@", to
connect to. The hostname may optionally be suffixed by a
container name, separated by ":", which
connects directly to a specific container on the specified
host. This will use SSH to talk to the remote machine manager
instance. Container names may be enumerated with
machinectl -H
HOST.
-M, --machine=¶Execute operation on a local container. Specify a container name to connect to.
-h, --help¶--version¶--no-pager¶Do not pipe output into a pager.
Example 1. Plots all dependencies of any unit whose name starts with
"avahi-daemon"
$ systemd-analyze dot 'avahi-daemon.*' | dot -Tsvg > avahi.svg
$ eog avahi.svgExample 2. Plots the dependencies between all known target units
systemd-analyze dot --to-pattern='*.target' --from-pattern='*.target' | dot -Tsvg > targets.svg $ eog targets.svg
The following errors are currently detected:
unknown sections and directives,
missing dependencies which are required to start the given unit,
man pages listed in
Documentation= which are not found in the
system,
commands listed in ExecStart=
and similar which are not found in the system or not
executable.
Example 3. Misspelt directives
$ cat ./user.slice
[Unit]
WhatIsThis=11
Documentation=man:nosuchfile(1)
Requires=different.service
[Service]
Desription=x
$ systemd-analyze verify ./user.slice
[./user.slice:9] Unknown lvalue 'WhatIsThis' in section 'Unit'
[./user.slice:13] Unknown section 'Service'. Ignoring.
Error: org.freedesktop.systemd1.LoadFailed:
Unit different.service failed to load:
No such file or directory.
Failed to create user.slice/start: Invalid argument
user.slice: man nosuchfile(1) command failed with code 16
Example 4. Missing service units
$ tail ./a.socket ./b.socket
==> ./a.socket <==
[Socket]
ListenStream=100
==> ./b.socket <==
[Socket]
ListenStream=100
Accept=yes
$ systemd-analyze verify ./a.socket ./b.socket
Service a.service not loaded, a.socket cannot be started.
Service b@0.service not loaded, b.socket cannot be started.