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PAPI

NAME

PAPI - Performance Application Programming Interface

SYNOPSIS

The PAPI Performance Application Programming Interface provides machine and operating system independent access to hardware performance counters found on most modern processors. Any of over 100 preset events can be counted through either a simple high level programming interface or a more complete low level interface from either C or Fortran. A list of the function calls in these interfaces is given below, with references to other pages for more complete details. For general information on the Fortran interface see: PAPIF(3)

Component PAPI

Beginning with version 3.9, PAPI supports extensions to count performance information on multiple simultaneous components. This capability is only provided in the low level interface. New or modified function calls are prefixed with an asterisk.

PAPI Presets

An extensive list of predefined events is implemented on all systems where they can be supported. For a list of these events, see: PAPI_presets(3)

PAPI Native Events

PAPI also supports interface functions for discovering the native events on a given platform. For more information on native events, see: PAPI_native(3)

High Level Functions

A simple interface for instrumenting end-user applications. Fully supported on both C and Fortran. See individual functions for details on usage.

 PAPI_num_counters(3) - get the number of hardware counters available on the system
 PAPI_flips(3) - simplified call to get Mflips/s (floating point instruction rate), real and processor time
 PAPI_flops(3) - simplified call to get Mflops/s (floating point operation rate), real and processor time
 PAPI_ipc(3) - gets instructions per cycle, real and processor time
 PAPI_accum_counters(3) - add current counts to array and reset counters
 PAPI_read_counters(3) - copy current counts to array and reset counters
 PAPI_start_counters(3) - start counting hardware events
 PAPI_stop_counters(3) - stop counters and return current counts
 

Note that the high-level interface is self-initializing. You can mix high and low level calls, but you must call either PAPI_library_init(3)orahighlevelroutinebefore calling a low level routine.

Low Level Functions

Advanced interface for all applications and performance tools. Some functions may be implemented only for C or Fortran. See individual functions for details on usage and support.

 PAPI_accum(3) - accumulate and reset hardware events from an event set
 PAPI_add_event(3) - add single PAPI preset or native hardware event to an event set
 PAPI_add_events(3) - add array of PAPI preset or native hardware events to an event set
 PAPI_assign_eventset_component(3)* - assign a component index to an existing but empty eventset
 PAPI_attach(3) - attach specified event set to a specific process or thread id
 PAPI_cleanup_eventset(3) - remove all PAPI events from an event set
 PAPI_create_eventset(3) - create a new empty PAPI event set
 PAPI_destroy_eventset(3) - deallocates memory associated with an empty PAPI event set
 PAPI_detach(3) - detach specified event set from a previously specified process or thread id
 PAPI_enum_event(3) - return the event code for the next available preset or natvie event
 PAPI_event_code_to_name(3) - translate an integer PAPI event code into an ASCII PAPI preset or native name
 PAPI_event_name_to_code(3) - translate an ASCII PAPI preset or native name into an integer PAPI event code
 PAPI_get_component_info(3)* - get information about the component features
 PAPI_get_dmem_info(3) - get dynamic memory usage information
 PAPI_get_event_info(3) - get the name and descriptions for a given preset or native event code
 PAPI_get_executable_info(3) - get the executable’s address space information
 PAPIF_get_exe_info(3) - Fortran version of PAPI_get_executable_info with different calling semantics
 PAPI_get_hardware_info(3) - get information about the system hardware
 PAPI_get_multiplex(3) - get the multiplexing status of specified event set
 PAPI_get_cmp_opt(3)* - query the component specific option settings of a specific event set
 PAPI_get_opt(3) - query the option settings of the PAPI library or a specific event set
 PAPIF_get_clockrate(3) - get the processor clockrate in MHz. Fortran only.
 PAPIF_get_domain(3) - get the domain of the specified eventset. Fortran only.
 PAPIF_get_granularity(3) - get the granularity of the specified eventset. Fortran only.
 PAPIF_get_preload(3) - get the 'LD_PRELOAD' environment equivalent. Fortran only.
 PAPI_get_real_cyc(3) - return the total number of cycles since some arbitrary starting point
 PAPI_get_real_usec(3) - return the total number of microseconds since some arbitrary starting point
 PAPI_get_shared_lib_info(3) - get information about the shared libraries used by the process
 PAPI_get_thr_specific(3) - return a pointer to a thread specific stored data structure
 PAPI_get_overflow_event_index(3) - decomposes an overflow_vector into an event index array
 PAPI_get_virt_cyc(3) - return the process cycles since some arbitrary starting point
 PAPI_get_virt_usec(3) - return the process microseconds since some arbitrary starting point
 PAPI_is_initialized(3) - return the initialized state of the PAPI library
 PAPI_library_init(3) - initialize the PAPI library
 PAPI_list_events(3) - list the events that are members of an event set
 PAPI_list_threads(3) - list the thread ids currently known to PAPI
 PAPI_lock(3) - lock one of two PAPI internal user mutex variables
 PAPI_multiplex_init(3) - initialize multiplex support in the PAPI library
 PAPI_num_components(3)* - return the number of components currently installed
 PAPI_num_cmp_hwctrs(3)* - return the number of hardware counters for a specified component
 PAPI_num_hwctrs(3) - return the number of hardware counters for the cpu
 PAPI_num_events(3) - return the number of events in an event set
 PAPI_overflow(3) - set up an event set to begin registering overflows
 PAPI_perror(3) - convert PAPI error codes to strings
 PAPI_profil(3) - generate PC histogram data where hardware counter overflow occurs
 PAPI_query_event(3) - query if a PAPI event exists
 PAPI_read(3) - read hardware events from an event set with no reset
 PAPI_register_thread(3) - inform PAPI of the existence of a new thread
 PAPI_remove_event(3) - remove a hardware event from a PAPI event set
 PAPI_remove_events(3) - remove an array of hardware events from a PAPI event set
 PAPI_reset(3) - reset the hardware event counts in an event set
 PAPI_set_debug(3) - set the current debug level for PAPI
 PAPI_set_cmp_domain(3)* - set the component specific default execution domain for new event sets
 PAPI_set_domain(3) - set the default execution domain for new event sets
 PAPIF_set_event_domain(3) - set the execution domain for a specific event set. Fortran only.
 PAPI_set_cmp_granularity(3)* - set the component specific default granularity for new event sets
 PAPI_set_granularity(3) - set the default granularity for new event sets
 PAPI_set_multiplex(3) - convert a standard event set to a multiplexed event set
 PAPI_set_opt(3) - change the option settings of the PAPI library or a specific event set
 PAPI_set_thr_specific(3) - save a pointer as a thread specific stored data structure
 PAPI_shutdown(3) - finish using PAPI and free all related resources
 PAPI_sprofil(3) - generate hardware counter profiles from multiple code regions
 PAPI_start(3) - start counting hardware events in an event set
 PAPI_state(3) - return the counting state of an event set
 PAPI_stop(3) - stop counting hardware events in an event set and return current events
 PAPI_strerror(3) - return a pointer to the error message corresponding to a specified error code
 PAPI_thread_id(3) - get the thread identifier of the current thread
 PAPI_thread_init(3) - initialize thread support in the PAPI library
 PAPI_unlock(3) - unlock one of two PAPI internal user mutex variables
 PAPI_unregister_thread(3) - inform PAPI that a previously registered thread is disappearing
 PAPI_write(3) - write counter values into counters
 

PAPI Utility Commands

A collection of simple utility commands is available in the \utils directory. See individual utilities for details on usage.

 papi_avail(1) - provides availability and detail information for PAPI preset events
 papi_clockres(1) - provides availability and detail information for PAPI preset events
 papi_cost(1) - provides availability and detail information for PAPI preset events
 papi_command_line(1) - executes PAPI preset or native events from the command line
 papi_decode(1) - decodes PAPI preset events into a csv format suitable for PAPI_encode_events
 papi_event_chooser(1) - given a list of named events, lists other events that can be counted with them
 papi_mem_info(1) - provides information on the memory architecture of the current processor
 papi_native_avail(1) - provides detailed information for PAPI native events
 

SEE ALSO

The PAPI Web site: http://icl.cs.utk.edu/papi

PAPIF(3), PAPI_presets(3), PAPI_native(3)