Red Hat Enterprise Linux 5 Administration Unleashed

452CHAPTER 22Monitoring and Tuning Applications. might be necessary for the event profiled. The unit masks for eachevent are listed with the events from the ophelp list. If the timer counter is used, aunit mask is not required.. set to 1 means that samples will be taken from kernel-space. If set to 0,kernel-space samples are not gathered.. set to 1 means that samples will be taken from user-space. If set to 0, userspacesamples are not gathered.. --separate= argument can be used to separate kernel and library samples.The following options are available:. none: Kernel and library profiles are not separated (default).. library: Separate library samples with the applications they are associatedwith (recommended).. kernel: Separate kernel and kernel module samples with the applications theyare associated with.. all: Equivalent to specifying both library and kernel.For example, to monitor the CPU_CLK_UNHALTED event with a sample rate of 950000 andunit mask of 0 in both the kernel- and user-space, showing library samples with the applicationsusing them, execute the following command:opcontrol --event=CPU_CLK_UNHALTED:950000:0:1:1 --separate=libraryThe settings in /root/.oprofile/daemonrc are modified accordingly after specifying anevent and options related to the event. If an event is not specified with the opcontrolcommand, the default event for the processor type is used. Table 22.1 shows the defaultevent for some of the processor types. These defaults are all time-based events. Thedefault event can also be retrieved with the following command:ophelp -d -c Replace with the processor type from the cat /dev/oprofile/cpu_typecommand. You can also combine these commands to get the default event:ophelp -d -c `cat /dev/oprofile/cpu_type`TABLE 22.1 Default Processor EventsProcessorIntel Pentium Pro, Pentium II, Pentium III, AMDAthlon, AMD64, Core2 DuoPentium 4 (HT and non-HT)Intel Itanium and Itanium 2ppc64/power4Default EventCPU_CLK_UNHALTEDGLOBAL_POWER_EVENTSCPU_CYCLESCYCLES