ocount (1) - Linux Manuals
ocount: Event counting tool for Linux
NAME
ocount - Event counting tool for LinuxSYNOPSIS
ocount [ options ] [ --system-wide | --process-list <pids> | --thread-list <tids> | --cpu-list <cpus> [ command [ args ] ] ]DESCRIPTION
ocount is an OProfile tool that can be used to count native hardware events occurring in either a given application, a set of processes or threads, a subset of active system processors, or the entire system. The data collected during a counting session is displayed to stdout by default or, optionally, to a file.
When counting multiple events, the kernel may not be able to count all events
simultaneously and, thus, may need to multiplex the counting of the events.
If this happens, the "Percent time enabled" column in the
ocount
output will be less than 100, but counts are scaled up to a 100% estimated value.
RUN MODES
One (and only one) of the following run modes must be specified. If you run ocount using a run mode other than command [args] , press Ctrl-c to stop ocount when finished counting (e.g., when the monitored process ends). If you background ocount (i.e., with '&') while using one these run modes, you must stop it in a controlled manner so that the data collection process can be shut down cleanly and final results can be displayed. Use kill -SIGINT <ocount-PID> for this purpose.- command [args]
-
The
command
is the application for which to count events.
args
are the input arguments required by the application.
The
command
and its arguments
must
be positioned at the
end of the command line, after all ocount options.
- --process-list / -p pids
-
Use this option to count events for one or more already-running applications, specified
via a comma-separated list (
pids
). Event counts will be collected for all children of the passed process(es)
as well.
- --thread-list / -r tids
-
Use this option to count events for one or more already-running threads, specified
via a comma-separated list (
tids
). Event counts will
not
be collected for any children of the passed thread(s).
- --system-wide / -s
-
This option is for counting events for all processes running on your system. You must
have root authority to run ocount in this mode.
- --cpu-list / -C cpus
-
This option is for counting events on a subset of processors on your system. You must
have root authority to run ocount in this mode. This is a comma-separated list, where each
element in the list may be either a single processor number or a range of processor numbers;
for example: '-C 2,3,4-11,15'.
OTHER OPTIONS
- --events / -e event1[,event2[,...]]
-
This option is for passing a comma-separated list of event specifications
for counting. Each event spec is of the form:
name[:unitmask[:kernel[:user]]]
Note: Do not include a count value in the event spec, as that parameter is only need when profiling.
-
You can specify unit mask values using either a numerical value (hex values
must
begin with "0x") or a symbolic name (if the
name=<um_name>
field is shown in the
ophelp
output). For some named unit masks, the hex value is not unique; thus, OProfile
tools enforce specifying such unit masks value by name.
If no unit mask is specified, the default unit mask value for the event is used.
Event names for certain processor types include a _GRP<n> suffix. For such cases, the --events option may be specified with or without the _GRP<n> suffix.
When no event specification is given, the default event for the running processor type will be used for counting. Use ophelp to list the available events for your processor type.
- --separate-thread / -t
- This option can be used in conjunction with either the --process-list or --thread-list option to display event counts on a per-thread (per-process) basis. Without this option, all counts are aggregated.
- NOTE: If new threads are started by the process(es) being monitored after counting begins, the counts for those threads are aggregated with their parent's counts.
- --separate-cpu / -c
-
This option can be used in conjunction with either the
--system-wide
or
--cpu-list
option
to display event counts on a per-cpu basis. Without this option, all counts are aggregated.
- --time-interval / -i num_seconds[:num_intervals]
-
Results collected for each time interval are printed every
num_seconds
instead of the default of one dump of cumulative event counts at the end of the run.
If
num_intervals
is specified,
ocount
exits after the specified number of intervals occur.
- --brief-format / -b
-
Use this option to print results in the following brief format:
[optional cpu or thread,]<event_name>,<count>,<percent_time_enabled>
[ <int> ,]< string >,< u64 >,< double >
-
If
--timer-interval
is specified, a separate line formatted as
timestamp,<num_seconds_since_epoch>
is printed ahead of each dump of event counts.
- --output-file / -f outfile_name
-
Results are written to
outfile_name
instead of interactively to the terminal.
- --verbose / -V
-
Use this option to increase the verbosity of the output.
- --version / -v
-
Show ocount version.
- --help / -h
-
Display brief usage message.
- --usage / -u
-
Display brief usage message.