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From: Jonathan Wakely <jwakely@redhat.com>
Date: Fri, 16 Jul 2021 12:17:23 +0100
Message-ID: <CACb0b4=_0op+uaKcf-_=q_Mk12cy0MdeUAa=FNHBF3S6zW7Gdw@mail.gmail.com>
Subject: Re: [PATCH] c++: implement C++17 hardware interference size
To: Noah Goldstein <goldstein.w.n@gmail.com>
Cc: Jason Merrill <jason@redhat.com>,
 "Richard Earnshaw (lists)" <Richard.Earnshaw@arm.com>, 
 "libstdc++" <libstdc++@gcc.gnu.org>, gcc-patches List <gcc-patches@gcc.gnu.org>,
 GNU C Library <libc-alpha@sourceware.org>
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On Fri, 16 Jul 2021 at 03:51, Noah Goldstein wrote:
> On intel x86 systems with a private L2 cache the spatial prefetcher
> can cause destructive interference along 128 byte aligned boundaries.
> https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf#page=60

Which is a good example of why these "constants" should never have
been standardized in the first place. Sigh.