More about Directory-Based Cache Coherence..

[amin...@gmail.com]

Hello,


More about Directory-Based Cache Coherence..

I have just written the following:

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About Snooping vs. Directory-based coherency..

Performance Scalability of a Multi-core Web Server

Read more here:

https://www.cse.wustl.edu/ANCS/slides/Bryan%20Veal%20ANCS%20Presentation.pdf


As you notice above that the Address bus saturation causes
poor scaling! And the Address Bus carries requests and
responses for data, called snoops, and more caches mean more sources
and more destinations for snoops that is causing the poor scaling.

So to solve the problem of poor scalability above, you have to use
Directory-based coherence that is a mechanism to handle Cache coherence problem in Distributed shared memory (DSM) a.k.a. Non-Uniform Memory Access (NUMA).

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And you have to know that Directory-Based Cache Coherence is scalable.

Read more here about it:

http://www.cs.cmu.edu/afs/cs/academic/class/15418-s19/www/lectures/13_directory.pdf

So you have to choose Directory-Based Cache Coherence that is scalable by using NUMA systems.


Thank you,
Amine Moulay Ramdane.