The readers-writers problem is an elementary problem in concurrency, and the typical solution involves the use of condition variables. The construct has its origins in 1974/1975 when Hoarse and Hansen formulated the idea of monitors.

Quoting ancient history serves no one any good. The world has move on -- a lot -- in the four decades since 1974/5. Especially with respect to concurrency and shared data.

"Both the mutual exclusion and producer-consumer protocols require waiting:

Read. Learn. Enjoy. Wait free algorithms.

Some choice quotes:

Wait-freedom is the strongest non-blocking guarantee of progress, combining guaranteed system-wide throughput with starvation-freedom. An algorithm is wait-free if every operation has a bound on the number of steps the algorithm will take before the operation completes.12 This property is critical for real-time systems and is always nice to have as long as the performance cost is not too high.
Wait-free algorithms were rare until 2011, both in research and in practice. However, in 2011 Kogan and Petrank15 presented a wait-free queue building on the CAS primitive, generally available on common hardware. Their construction expanded the lock-free queue of Michael and Scott,16 which is an efficient queue often used in practice. A follow-up paper by Kogan and Petrank17 provided a methodology for making wait-free algorithms fast and used this methodology to make the wait-free queue practically as fast as its lock-free counterpart. A subsequent paper by Timnat and Petrank18 provided an automatic mechanism for generating wait-free data structures from lock-free ones. Thus, wait-free implementations are now available for many data-structures.
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: Threads sharing global variable by BrowserUk
in thread Threads sharing global variable by Anonymous Monk

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