Editing Distributed computing (section)

===Other problems===
Traditional computational problems take the perspective that the user asks a question, a computer (or a distributed system) processes the question, then produces an answer and stops. However, there are also problems where the system is required not to stop, including the [[dining philosophers problem]] and other similar [[mutual exclusion]] problems. In these problems, the distributed system is supposed to continuously coordinate the use of shared resources so that no conflicts or [[deadlock (computer science)|deadlock]]s occur.

There are also fundamental challenges that are unique to distributed computing, for example those related to ''fault-tolerance''. Examples of related problems include [[Consensus (computer science)|consensus problems]],<ref>{{harvtxt|Lynch|1996}}, Sections 5–7. {{harvtxt|Ghosh|2007}}, Chapter 13.</ref> [[Byzantine fault tolerance]],<ref>{{harvtxt|Lynch|1996}}, p. 99–102. {{harvtxt|Ghosh|2007}}, p. 192–193.</ref> and [[self-stabilisation]].<ref>{{harvtxt|Dolev|2000}}. {{harvtxt|Ghosh|2007}}, Chapter 17.</ref>

Much research is also focused on understanding the ''asynchronous'' nature of distributed systems:
* [[Synchronizer (algorithm)|Synchronizers]] can be used to run synchronous algorithms in asynchronous systems.<ref>{{harvtxt|Lynch|1996}}, Section 16. {{harvtxt|Peleg|2000}}, Section 6.</ref>
* [[Logical clock]]s provide a causal [[happened-before]] ordering of events.<ref>{{harvtxt|Lynch|1996}}, Section 18. {{harvtxt|Ghosh|2007}}, Sections 6.2–6.3.</ref>
* [[Clock synchronization]] algorithms provide globally consistent physical time stamps.<ref>{{harvtxt|Ghosh|2007}}, Section 6.4.</ref>

Note that in distributed systems, [[Latency (engineering)|latency]] should be measured through "99th percentile" because "median" and "average" can be misleading.<ref>{{Cite book |title=Foundations of Data Intensive Applications Large Scale Data Analytics Under the Hood |year=2021 |isbn=9781119713012 |last1=Kamburugamuve |first1=Supun |last2=Ekanayake |first2=Saliya |publisher=John Wiley & Sons }}</ref>