ocount(1) General Commands Manual ocount(1)
ocount - Event counting tool for Linux
ocount [ options ] [ --system-wide | --process-list <pids> | --thread-list <tids> | --cpu-list <cpus> [ command [ args ] ] ]
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.
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.
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
--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'.
--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:
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 aggre-
gated 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
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.
$ ocount make
This man page is current for oprofile-0.9.9.
oprofile 0.9.9 Tue 10 June 2014 ocount(1)