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papi_num_cmp_hwctrs(3) [centos man page]

PAPI_num_cmp_hwctrs(3)						       PAPI						    PAPI_num_cmp_hwctrs(3)

NAME
PAPI_num_cmp_hwctrs - Return the number of hardware counters for the specified component. SYNOPSIS
Detailed Description PAPI_num_cmp_hwctrs() returns the number of counters present in the specified component. By convention, component 0 is always the cpu. On some components, especially for CPUs, the value returned is a theoretical maximum for estimation purposes only. It might not be possible to easily create an EventSet that contains the full number of events. This can be due to a variety of reasons: 1). Some CPUs (especially Intel and POWER) have the notion of fixed counters that can only measure one thing, usually cycles. 2). Some CPUs have very explicit rules about which event can run in which counter. In this case it might not be possible to add a wanted event even if counters are free. 3). Some CPUs halve the number of counters available when running with SMT (multiple CPU threads) enabled. 4). Some operating systems 'steal' a counter to use for things such as NMI Watchdog timers. The only sure way to see if events will fit is to attempt adding events to an EventSet, and doing something sensible if an error is generated. PAPI_library_init() must be called in order for this function to return anything greater than 0. C Interface: #include <papi.h> int PAPI_num_cmp_hwctrs(int cidx ); Parameters: cidx -- An integer identifier for a component. By convention, component 0 is always the cpu component. Example * // Query the cpu component for the number of counters. * printf( * Returns: On success, this function returns a value greater than zero. A zero result usually means the library has not been initialized. Author Generated automatically by Doxygen for PAPI from the source code. Version 5.2.0.0 Tue Jun 17 2014 PAPI_num_cmp_hwctrs(3)

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PAPI_set_cmp_domain(3)						       PAPI						    PAPI_set_cmp_domain(3)

NAME
PAPI_set_cmp_domain - Set the default counting domain for new event sets bound to the specified component. SYNOPSIS
Detailed Description @par C Prototype: int PAPI_set_cmp_domain( int domain, int cidx ); @param domain one of the following constants as defined in the papi.h header file @arg PAPI_DOM_USER User context counted @arg PAPI_DOM_KERNEL Kernel/OS context counted @arg PAPI_DOM_OTHER Exception/transient mode counted @arg PAPI_DOM_SUPERVISOR Supervisor/hypervisor context counted @arg PAPI_DOM_ALL All above contexts counted @arg PAPI_DOM_MIN The smallest available context @arg PAPI_DOM_MAX The largest available context @arg PAPI_DOM_HWSPEC Something other than CPU like stuff. Individual components can decode low order bits for more meaning @param cidx An integer identifier for a component. By convention, component 0 is always the cpu component. Return values: PAPI_OK PAPI_EINVAL One or more of the arguments is invalid. PAPI_ENOCMP The argument cidx is not a valid component. PAPI_set_cmp_domain sets the default counting domain for all new event sets in all threads, and requires an explicit component argument. Event sets that are already in existence are not affected. To change the domain of an existing event set, please see PAPI_set_opt. The reader should note that the domain of an event set affects only the mode in which the counter continues to run. Counts are still aggregated for the current process, and not for any other processes in the system. Thus when requesting PAPI_DOM_KERNEL , the user is asking for events that occur on behalf of the process, inside the kernel. Example: int ret; // Initialize the library ret = PAPI_library_init(PAPI_VER_CURRENT); if (ret > 0 && ret != PAPI_VER_CURRENT) { fprintf(stderr,"PAPI library version mismatch!0); exit(1); } if (ret < 0) handle_error(ret); // Set the default domain for the cpu component ret = PAPI_set_cmp_domain(PAPI_DOM_KERNEL,0); if (ret != PAPI_OK) handle_error(ret); ret = PAPI_create_eventset(&EventSet); if (ret != PAPI_OK) handle_error(ret); * See Also: PAPI_set_domain PAPI_set_granularity PAPI_set_opt PAPI_get_opt Author Generated automatically by Doxygen for PAPI from the source code. Version 5.2.0.0 Tue Jun 17 2014 PAPI_set_cmp_domain(3)
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