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CentOS 7.0 - man page for systemd-analyze (centos section 1)

SYSTEMD-ANALYZE(1)						  systemd-analyze						SYSTEMD-ANALYZE(1)

NAME
systemd-analyze - Analyze system boot-up performance
SYNOPSIS
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]
DESCRIPTION
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.
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, 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". --no-pager Do not pipe output into a pager.
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-pattern='*.target' | dot -Tsvg > targets.svg $ eog targets.svg
ENVIRONMENT
$SYSTEMD_PAGER Pager to use when --no-pager is not given; overrides $PAGER. Setting this to an empty string or the value "cat" is equivalent to passing --no-pager.
SEE ALSO
systemd(1), systemctl(1) systemd 208 SYSTEMD-ANALYZE(1)