Memory Consistency: Compiler and Programming Languages

This lecture delves into memory consistency, exploring the relationship between coherence and consistency, the challenges of weak consistency, and the implementation of sequential consistency. The instructor discusses the impact of memory models on performance, the execution with store buffers, and the use of fence operations to disable processor consistency. Real-world examples illustrate weak consistency in CPUs, the ARM memory model, and the importance of language-level consistency. The lecture emphasizes the need for end-to-end guarantees in memory ordering and the implications of data races in programming languages like Java and C++11. The instructor also covers the concept of 'Data Race Free Sequential Consistency' and the significance of synchronization variables in ensuring memory consistency throughout the stack.