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by malkia 5164 days ago
Any refs, docs about this behavior? First time hearing it. How does it work with MMU, protected memory, or external memory mapped as normal one?

I know a bit about prefetch, and it's variants, but haven't directly used in 10 years (I was on a software project that had one of the first Katmai's, back in 1999 to do some bilinear/bicubic texture filtering for a media/drawing application, and had to code extensively in mmx assembly back then).

1 comments

> Any refs, docs about this behavior? First time hearing it. How does it work with MMU, protected memory, or external memory mapped as normal one?

edit: try to look for performance tuning guides for your CPU architecture, there might be some details about systems like this.

Nope. Some might exist but this stuff is generally considered trade secrets. A patent search might yield something. You can find some material about speculative execution, branch prediction, prefetching, etc but the real beef is hidden somewhere in Intel's (and their competitors') vaults.

It's all supposed to be transparent to the programmer so there's no need to write and release detailed public documentation about it.

As I said earlier, I have no idea how they work (or do they even exist), but I'll give a handwaving example of how they _could_ work.