Is there a way to disable the mmu for a specific block memory?

If we can access some block memory without mmu, while accessing other memory with mmu, a good performance gain can be achieved. I have read the intelx86_64 manual, and only to find that mission seems impossible...Or perhaps can we disble the mmu to work when accessing the specifice memory?

Can someone tell the answer to开发者_C百科 me ? Thanks!

Short answer: no, you cannot.

Long answer: you can write a kernel module that switches the CPU to 32-bit mode (if in 64-bit mode) and disables paging, while remaining in protected mode. During that time, you would be able to run only pure computations, i.e., no input/output (including networking) would be possible. (Presuming that you want to be able to restore the OS kernel and other running applications to their original state, which is essentially a must if you want to be able to save the results of your computations.)