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[pavandsp]

Hi

I am trying to profile a simple (for loop)code in OpenCL.

I used clGetEventProfilingInfo to get the start and end time.But i am getting weired values start time=-1775338701 ,end time=19927,and the diff=start-end=1046102520 and the  param_value_size_ret=19939.

I called the api clGetEventProfilingInfo after clEnqueueNDRangekernel and clwaitForevents apis.

My Config=Linux Ubuntu 9.04,Intel CPU.

My Question is :1.How come start time is -ve

2.end time <start time.

psuedo profile code:

clGetEventProfilingInfo (events[0],CL_PROFILING_COMMAND_START,sizeof(cl_ulong,&starttime,&length));

clGetEventProfilingInfo (events[0],CL_PROFILING_COMMAND_END,sizeof(cl_ulong,&end time,&length));

cl_ulong diff=endtime-start time;

printf("start time=%d end =%d diff=%d length=%d",start,end ,diff,length);

do i need to do something in kernel file?

Thanks

Pavan

[nou]

did you enable profiling when you create command queue?

%d in printf expect 32 bit int. use %llu instead.

[Fr4nz]

Originally posted by: pavandsp

[cut]

do i need to do something in kernel file? Thanks Pavan

Times returned by profiler are expressed in nanoseconds (10^-9 sec.), that's why you see those values. After you do endtime-starttime you have to scale the result in seconds.

[genaganna]

Originally posted by: pavandsp Hi

I am trying to profile a simple (for loop)code in OpenCL.

I used clGetEventProfilingInfo to get the start and end time.But i am getting weired values start time=-1775338701 ,end time=19927,and the diff=start-end=1046102520 and the  param_value_size_ret=19939.

I called the api clGetEventProfilingInfo after clEnqueueNDRangekernel and clwaitForevents apis.

My Config=Linux Ubuntu 9.04,Intel CPU.

My Question is :1.How come start time is -ve

2.end time

psuedo profile code:

clGetEventProfilingInfo (events[0],CL_PROFILING_COMMAND_START,sizeof(cl_ulong,&starttime,&length));

clGetEventProfilingInfo (events[0],CL_PROFILING_COMMAND_END,sizeof(cl_ulong,&end time,&length));

cl_ulong diff=endtime-start time;

printf("start time=%d end =%d diff=%d length=%d",start,end ,diff,length);

               Could you please post test case which shows the problem? 

     Do i need to do something in kernel file?

     Nothing is required in kernel file.