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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.lang.forth
Subject: Re: Parallel Forth on a 44 core machine
Date: Sun, 18 Aug 2024 15:14:52 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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mhx@iae.nl (mhx) writes:
>Do you know if shared memory as provided by the OS (or Windows)
>has these problems too?

Shared memory has false sharing problems, however that sharing is
arranged.  The slowdown comes from the hardware.  See
<https://en.wikipedia.org/wiki/False_sharing>.

The I-cache/D-cache ping-pong when you have writable data close to
executed code on AMD64 is also false sharing, this time within one
core.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
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