5 ms·
Why doesn’t the kernel have access to AVX optimised memory copy instructions?
by spockz 6y ago
Why doesn’t the kernel have access to AVX optimised memory copy instructions?
- jws 6y agoThe size of the state required to be saved and restored on each system call makes it a losing proposition.
- PaulDavisThe1st 6y agoEach context switch, not syscall.
- topspin 6y agoThe kernel does have access to these instructions. It is a deliberate choice by kernel developers not to use them in the case discussed here. In other cases the kernel does use such instructions.
- jiggawatts 6y agoStupid question: Does the entire AVX state need to be saved and restored for a memcpy routine? It seems like it would be sufficient to save at most a couple of registers for a tight copy loop...