RE: [PATCH] mm: clear 1G pages with streaming stores on x86

David Laight
2020-03-11T15:07:13Z

From: Andi Kleen
> Sent: 09 March 2020 15:39
...
> There's a cautious tale of the old crappy RAID5 XOR assembler functions which
> were optimized a long time ago for the Pentium1, and stayed around,
> even though the compiler could actually do a better job.

Or the amd64 asm loop for doing the IP checksum.
I doubt it was even the fastest version when it was written.
A whole set of Intel cpus can run twice as fast as that version
with less loop unrolling (and associated code for 'odd' lengths).

David

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