systemd-bootchartsystemdDeveloperAukeKokauke-jan.h.kok@intel.comsystemd-bootchart1systemd-bootchartBoot performance analysis graphing toolDescriptionSystemd-bootchart is an boot time analysis tool. It represents
various aspects of the system as graph elements. These graph
elements allow the user to determine resource usage, efficiency
and performance issues.Invocationsystemd-bootchart can be invoked in several different ways:Kernel invocationThe kernel can invoke systemd-bootchart
instead of the init process. In itself, systemd-bootchart
will invoke /sbin/init if invoked in
this matter.Started as a standalone programOne can execute systemd-bootchart as
normal application from the commandline. In this mode
it is highly recommended to pass the "-r" flag in order
to not graph the time elapsed since boot and before
systemd-bootchart was started, as it may result in
extremely large graphs.
OptionsSpecify the amount of samples to
record total before bootchart exits. Each sample will
record at intervals defined by --freq.Specify the sample log frequency.
This can be a fractional number, but must be larger than
0.0. Most systems can cope with values under 25-50 without
impacting boot time severely.Use relative times instead of absolute
times. This is useful for using bootchart at post-boot
time to profile an already booted system, otherwise the
graph would become extremely large. If set, the
horizontal axis starts at the first recorded sample
instead of time=0.0.Disable filtering of tasks tasks that
did not contribute significantly to the boot. Processes
that are too short-lived (only seen in one sample) or
that do not consume any significant CPU time (less than
0.001sec) will not be displayed in the output graph.
Configures the output folder for writing
the graphs. By default, bootchart writes the graphs to
/run/log.Set init binary to run. Defaults to
/sbin/init.
Enable logging and graphing
of processes PSS memory consumption.Enable logging and graphing
of the kernel random entropy pool size.Horizontal scaling factor for all variable
graph components.Vertical scaling factor for all variable
graph components.OutputSystemd-bootchart generates SVG graphs. In order to render these
on a graphical display any SVG capable viewer can be used. It should be
noted that the SVG render engines in most browsers (including Chrome
and Firefox) are many times faster than dedicated graphical applications
like Gimp and Inkscape. Just point your browser at "file:///var/log"!
See Alsobootchart.conf5