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Winter 2014 SPO600 Weekly Schedule

118 bytes added, 17:20, 5 February 2014
Memory Barriers
'''Memory Barriers''' ensure that memory accesses are sequenced so that multiple threads, processes, cores, or IO devices see a predictable view of memory.
* Leif Lindholm provides an excellent explanation of memory barriers.
** Blog series - I recommend this series - , especially the introduction - , as the clearest a very clear explanation of the issuememory barrier issues.
*** Part 1 - [http://community.arm.com/groups/processors/blog/2011/03/22/memory-access-ordering--an-introduction Memory Access Ordering - An Introduction]
*** Part 2 - [http://community.arm.com/groups/processors/blog/2011/04/11/memory-access-ordering-part-2--barriers-and-the-linux-kernel Memory Access Ordering Part 2 - Barriers and the Linux Kernel]
*** [http://elinux.org/images/f/fa/Software_implications_memory_systems.pdf Slides]
*** [http://free-electrons.com/pub/video/2010/elce/elce2010-lindholm-memory-450p.webm Video]
* [http://www.rdrop.com/users/paulmck/scalability/paper/whymb.2010.07.23a.pdf Memory Barriers - A Hardware View for Software Hackers] - This is a highly-rated article paper that explains memory barrier issues- as the title suggests, it is designed to describe the hardware origin of the problem to software developers. Despite the fact that it is an introduction to the topic, it is still very technical.
* [http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka14041.html ARM Technical Support Knowlege Article - In what situations might I need to insert memory barrier instructions?] - Note that there are some additional mechanisms present in ARMv8 aarch64, including Acquire/Release.
* [https://www.kernel.org/doc/Documentation/memory-barriers.txt Kernel Documentation on Memory Barriers] - discusses the memory barrier issue generally, and the solutions used within the Linux kernel. This is part of the kernel documentation.