systemd-analyze

systemd
Developer Lennart Poettering lennart@poettering.net
Developer Harald Hoyer harald@redhat.com
systemd-analyze 1
systemd-analyze Analyze system boot-up performance
`systemd-analyze OPTIONS time` `systemd-analyze OPTIONS blame` `systemd-analyze OPTIONS critical-chain` `systemd-analyze OPTIONS plot > file.svg` `systemd-analyze OPTIONS dot pattern...`

## Description

`systemd-analyze` may be used to determine system boot-up performance of the current boot.

`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` prints a tree of the time critical chain of units. 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` Generate 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.

If no command is passed `systemd-analyze time` is implied.

## Options

The following options are understood:

`-h`
`--help`

  Prints a short help text and exits.

`--user`

  Shows performance data of user sessions instead of the system manager.

`--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, shows dependencies of all these types.

`--from-pattern=`
`--to-pattern=`

  When used in conjunction with the `dot` command (see above), selects which relationships are shown in the dependency graph. They both require glob 7 patterns as arguments, which are matched against lefthand and righthand, respectively, nodes of a relationship. Each of these can be used more than once which means a unit name must match one of 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, i.e. "50ms".

## Exit status

On success 0 is returned, a non-zero failure code otherwise.

## Examples

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-patter='*.target' | dot -Tsvg > targets.svg
    $ eog targets.svg

## See Also

systemd 1, systemctl 1