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SunOS man pages : cpustat (1)

Maintenance Commands                                  cpustat(1M)


cpustat - monitor system behavior using CPU performance counters


cpustat -c eventspec [ -c eventspec ] ... [ -ntD ] [ interval [ count ] ] cpustat -h


The cpustat utility allows CPU performance counters to be used to monitor the overall behavior of the CPUs in the sys- tem. If interval is specified, cpustat samples activity every interval seconds, repeating forever. If a count is speci- fied, the statistics are repeated count times. If neither are specified, an interval of five seconds is used, and there is no limit to the number of samples that will be taken.


The following options are supported: -c eventspec Specify a set of events for the CPU performance counters to monitor. The syntax of these event specif- ication can be determined using the -h option to cause the usage message to be generated. The semantics of these event specifications can be determined by read- ing the CPU manufacturers documentation for the events. See cpc_strtoevent(3CPC) for a description of the syntax. Multiple -c options may be specified, in which case the command cycles between the different event set- tings on each sample. -D Enable debug mode. -h Print an extensive help message on how to use the utility and how to program the processor-dependent counters. -n Omit all header output (useful if cpustat is the beginning of a pipeline). -t Print an additional column of processor cycle counts, if available on the current architecture. SunOS 5.8 Last change: 14 Sep 1999 1 Maintenance Commands cpustat(1M)


A closely related utility, cputrack(1), can be used to moni- tor the behavior of individual applications with little or no interference from other activities on the system. The cpustat utility must be run by the super-user, as there is an intrinsic conflict between the use of the CPU perfor- mance counters system-wide by cpustat and the use of the CPU performance counters to monitor an individual process (for example, by cputrack.) Once any instance of this utility has started, no further per-process or per-LWP use of the counters is allowed until the last instance of the utility terminates. The times printed by the command correspond to the wallclock time when the hardware counters were actually sampled, instead of when the program told the kernel to sample them. The time is derived from the same timebase as gethrtime(3C). The processor cycle counts enabled by the -t option always apply to both user and system modes, regardless of the set- tings applied to the performance counter registers. The output of cpustat is designed to be readily parseable by nawk(1) and perl(1), thereby allowing performance tools to be composed by embedding cpustat in scripts. Alternatively, tools may be constructed directly using the same APIs that cpustat is built upon using the facilities of libcpc(3LIB). See cpc(3CPC). The cpustat utility only monitors the CPUs that are accessi- ble to it in the current processor set. Thus several instances of the utility can be running on the CPUs in dif- ferent processor sets. See psrset(1M) for more information about processor sets. Because cpustat uses LWPs bound to CPUs, the utility may have to terminated before the configuration of the relevant processor can be changed.


By running the cpustat command, the superuser will forcibly invalidate all existing performance counter context. This may in turn cause all invocations of the cputrack command, and other users of performance counter context, to exit prematurely with unspecified errors.


See attributes(5) for descriptions of the following attri- butes: SunOS 5.8 Last change: 14 Sep 1999 2 Maintenance Commands cpustat(1M) ____________________________________________________________ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | | Availability | SUNWcpcu | | Interface Stability | Evolving | |_____________________________|_____________________________|


cputrack(1), nawk(1), perl(1), iostat(1M), prstat(1M), psrset(1M), vmstat(1M), cpc(3CPC), cpc_strtoevent(3CPC), gethrtime(3C), libcpc(3LIB), attributes(5) Sun Microelectronics UltraSPARC I&II User's Manual, January 1997, STP1031, Intel Architecture Software Developer's Manual, Volume 3: System Programmers Guide, 243192, SunOS 5.8 Last change: 14 Sep 1999 3