- cl_int clGetEventProfilingInfo(cl_event event, cl_profiling_info param_name, size_t param_value_size, void *param_value, size_t *param_value_size_ret);
PARAMETERS
event
-
- Specifies the event object.
param_name
- Specifies the profiling data to query. The list of supported param_name types and the information returned in param_value by clGetEventProfilingInfo is described in the table of parameter queries below.
param_value_size
- Specifies the size in bytes of memory pointed to by param_value. This size must be ≥ size of return type as described in the table below.
param_value
- A pointer to memory where the appropriate result being queried is returned. if param_value is NULL, it is ignored.
param_value_size_ret
- Returns the actual size in bytes of data copied to param_value. If param_value_size_ret is NULL, it is ignored.
-
The following is a table of
clGetEventProfilingInfo
parameter queries
cl_profiling_info Return Type Info. returned in param_value CL_PROFILING_COMMAND_QUEUED cl_ulong A 64-bit value that describes the current device time counter in nanoseconds when the command identified by event is enqueued in a command-queue by the host. CL_PROFILING_COMMAND_SUBMIT cl_ulong A 64-bit value that describes the current device time counter in nanoseconds when the command identified by event that has been enqueued is submitted by the host to the device associated with the command-queue. CL_PROFILING_COMMAND_START cl_ulong A 64-bit value that describes the current device time counter in nanoseconds when the command identified by event starts execution on the device. CL_PROFILING_COMMAND_END cl_ulong A 64-bit value that describes the current device time counter in nanoseconds when the command identified by event has finished execution on the device.
NOTES
The unsigned 64-bit values returned can be used to measure the time in nano-seconds consumed by OpenCL commands.
OpenCL devices are required to correctly track time across changes in device frequency and power states. The CL_DEVICE_PROFILING_TIMER_RESOLUTION specifies the resolution of the timer i.e. the number of nanoseconds elapsed before the timer is incremented.
Event objects can be used to capture profiling information that measure execution time of a command. Profiling of OpenCL commands can be enabled either by using a command-queue created with CL_QUEUE_PROFILING_ENABLE flag set in properties argument to clCreateCommandQueue(3clc).
ERRORS
Returns CL_SUCCESS if the function is executed successfully and the profiling information has been recorded. Otherwise, it returns one of the following errors:
- • CL_PROFILING_INFO_NOT_AVAILABLE if the CL_QUEUE_PROFILING_ENABLE flag is not set for the command-queue, if the execution status of the command identified by event is not CL_COMPLETE or if event is a user event object.
- • CL_INVALID_VALUE if param_name is not valid, or if size in bytes specified by param_value_size is < size of return type as described in the above table and param_value is not NULL.
- • CL_INVALID_EVENT if event is a not a valid event object.
- • CL_OUT_OF_RESOURCES if there is a failure to allocate resources required by the OpenCL implementation on the device.
- • CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the OpenCL implementation on the host.
SPECIFICATION
m[blue]OpenCL Specificationm[][1]
AUTHORS
The Khronos Group
COPYRIGHT
Copyright © 2007-2011 The Khronos Group Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and/or associated documentation files (the "Materials"), to deal in the Materials without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Materials, and to permit persons to whom the Materials are furnished to do so, subject to the condition that this copyright notice and permission notice shall be included in all copies or substantial portions of the Materials.
NOTES
- 1.
-
OpenCL Specification
- page 190, section 5.12 - Profiling Operations on Memory Objects and Kernels