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[mohit2710]

Hi,

I am a college student trying to understand the new opencl environment...

I am using an intel xeon CPU E5405 @2.00GHz, quad core using linux(ubuntu) operating system.

I have been studying the Matrix Multiplication code...In which I have some problems...

1. When I increase the blocksize to 64....an error "Device does not support requested number of work items"  comes....What does this error indicate about my hardware....

The maximum workgroupsize =1024 for my device..Does this indicate that my device has 1024 processing elements?

2.When i keep blocksize=32, does this mean that 32*32 elemnts are computed in parallel for a single compute unit?

3. I am curious to know what exactly is the definition of a processing element in reference to a CPU?

Any kind of help is appreciated.

[nou]

1. when you run CLInfo sample you can find this
    Max work items dimensions:             3
    Max work items[0]:                 1024
    Max work items[1]:                 1024
    Max work items[2]:                 1024
  Max work group size:                 1024

it mean you can run maximum 3D addresed task. and each work-groub can be maxmimu 1024 in one dimension. but multiply of work-group sizes must be below "Max work group size"

when you specifi 64 then you want compute 64*64 = 4096 element in one work-group. that exceed 1024 limit.

2. no it mean that it is compute 32*32 element in one work-group. one work-group can share local memory.