Re: [PATCH v4 3/3] mm/free_pcppages_bulk: prefetch buddy while not holding lock

From: Dave Hansen
Date: Fri Mar 02 2018 - 13:00:35 EST


On 03/02/2018 09:55 AM, Vlastimil Babka wrote:
> It's even stranger to me. Struct page is 64 bytes these days, exactly a
> a cache line. Unless that changed, Intel CPUs prefetched a "buddy" cache
> line (that forms an aligned 128 bytes block with the one we touch).

I believe that was a behavior that was specific to the Pentium 4
"Netburst" era. I don't think the 128-byte line behavior exists on
modern Intel cpus.