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 may be used to determine system boot-up performance statistics and retrieve other state and tracing information from the system and service manager.
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)).
If no command is passed, systemd-analyze time is implied.
The following options are understood:
--user¶Shows performance data of user sessions instead of the system manager.
--system¶Shows performance data of the system manager. 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. They both require glob(7) patterns as arguments, which are matched against left-hand and right-hand, respectively, nodes of a relationship. Each of these can be used more than once, which means a unit name must match one of the given values.
--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".
-H, --host=¶Execute the operation remotely. Specify a hostname, or
username and hostname separated by "@", to
connect to. This will use SSH to talk to the remote machine
manager instance.
-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.
This plots all dependencies of any unit whose
name starts with "avahi-daemon.":
$ systemd-analyze dot 'avahi-daemon.*' | dot -Tsvg > avahi.svg $ eog avahi.svg
This plots the dependencies between all known target units:
systemd-analyze dot --to-pattern='*.target' --from-pattern='*.target' | dot -Tsvg > targets.svg $ eog targets.svg