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How much private memory does a PE has ?

The device that I use is ATI Radeon 5700. Thanks.

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The hardward itself limits private memory to the amount of global memory. The software limits it to 64KB of memory per thread on this device. However, you don't want to use any unless you absolutely have to for performance reasons as it is uncached device memory and not fast memory.

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The hardward itself limits private memory to the amount of global memory. The software limits it to 64KB of memory per thread on this device. However, you don't want to use any unless you absolutely have to for performance reasons as it is uncached device memory and not fast memory.

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Well, unless you consider registers ...

MicahVillmow wrote:

However, you don't want to use any unless you absolutely have to for performance reasons as it is uncached device memory and not fast memory.

While conceptually the same at the OpenCL level, registers and private memory are drastically different. I view questions about private memory to be different than questions about the register file. While private memory can be optimized into the register file in some situations, there are many more that cannot.

Well conversely, PE's don't actually have any private memory apart from registers.  i.e. 'privately marked' memory is just allocated from the general uncached global heap if it doesn't fit in registers.

If one is expecting a high-performance localised-per-cu 'private' - which seems to be what most people expect when they ask this question -  then registers are the only private memory one is interested in.