Thread: Intel Xeon PHI?
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Old 2020-12-02, 20:09   #147
kriesel's Avatar
Mar 2017
US midwest

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Originally Posted by VBCurtis View Post
I interpreted that Colfax document as explaining that cache mode would really be a cache, and not seen by the OS as main memory; while flat would treat the on-package RAM as main memory but a separate space from the DDR4 module.
I concur after a light reading of it. Somehow the BIOS, Windows 10 and prime95 knew what to do with the MCDRAM in the absence of any DIMMS in my system, and use it as addressable memory. Sounds like a 1-legged flat mode imposed by the OS to me. Windows and Linux and prime95 and presumably Mlucas have been dealing with multiple NUMA banks for a while now. Looking at both source codes for how dual processor package systems are handled might be educational.

Last fiddled with by kriesel on 2020-12-02 at 20:17
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