Red Hat Enterprise Linux 5 Administration Unleashed

OProfile 453TABLE 22.1Continuedppc64/power5ppc64/970ppc64/power5+CYCLESCYCLESCYCLESStarting OProfileFinally, to start the sampling process, execute the following as root:22opcontrol --startThe settings from /root/.oprofile/daemonrc are used, and the daemon oprofiled isstarted. The output should look similar to Listing 22.4.LISTING 22.4Starting OProfileUsing default event: CPU_CLK_UNHALTED:100000:0:1:1Using 2.6+ OProfile kernel interface.Reading module info.Using log file /var/lib/oprofile/oprofiled.logDaemon started.Profiler running.Gathering the SamplesThe samples collected are written to the /var/lib/oprofile/samples/ directory, and/var/lib/oprofile/oprofiled.log is used as the log file for the daemon.To force the sample data to be written, use the following command as root:opcontrol --save=The /var/lib/oprofile/samples// directory is created, and the sample data iswritten to the directory.Analyzing the SamplesBefore analyzing the samples in the /var/lib/oprofile/samples/ directory, make sure alldata has been written out by executing the following command as root (data is flushed tothe /var/lib/oprofile/samples/current/ directory):opcontrol --dumpAfter running the OProfile daemon to collect your data and writing the data to disk,OProfile can be stopped by executing the following command as root:opcontrol --stop