Concurrency control > Concurrency control in databases > Why is concurrency control needed?: https://en.m.wikipedia.org/wiki/Concurrency_control#Why_is_concur

Concurrency control > Concurrency control in databases > Why is concurrency control needed?: https://en.m.wikipedia.org/wiki/Concurrency_control#Why_is_concurrency_control_needed https://en.m.wikipedia.org/wiki/Concurrency_control#Why_is_c...? Locks (computer science) > Disadvantages: https://en.wikipedia.org/wiki/Lock_(computer_science)#Disadvantages https://en.wikipedia.org/wiki/Lock_(computer_science)#Disadv... Two-phase locking (2PL) https://en.wikipedia.org/wiki/Two-phase_locking https://en.wikipedia.org/wiki/Two-phase_locking Two-phase commit protocol (2PC) https://en.wikipedia.org/wiki/Two-phase_commit_protocol https://en.wikipedia.org/wiki/Two-phase_commit_protocol Paxos: https://en.wikipedia.org/wiki/Paxos_(computer_science) https://en.wikipedia.org/wiki/Paxos_(computer_science) Raft: https://en.wikipedia.org/wiki/Raft_(algorithm) https://en.wikipedia.org/wiki/Raft_(algorithm) Consensus (computer science) https://en.wikipedia.org/wiki/Consensus_(computer_science) https://en.wikipedia.org/wiki/Consensus_(computer_science) Spanner: https://en.wikipedia.org/wiki/Spanner_(database) https://en.wikipedia.org/wiki/Spanner_(database) Non-blocking algorithm; "lock-free concurrency", "wait-free" https://en.wikipedia.org/wiki/Non-blocking_algorithm https://en.wikipedia.org/wiki/Non-blocking_algorithm "Ask HN: Why don't PCs have better entropy sources?" [for generating txids/uuids] https://news.ycombinator.com/item?id=30877296 https://news.ycombinator.com/item?id=30877296 "100-Gbit/s Integrated Quantum Random Number Generator Based on Vacuum Fluctuations" https://link.aps.org/doi/10.1103/PRXQuantum.4.010330 https://link.aps.org/doi/10.1103/PRXQuantum.4.010330 Re: tests of randomness: https://mail.python.org/archives/list/python-ideas@python.org/message/T3CM5FIVVUZRDP7RQ2QRNQTPWUR4WAR7/ https://mail.python.org/archives/list/python-ideas@python.or... TIL there's a regular heartbeat in the quantum foam; there's a regular monotonic heartbeat in the quantum Rydberg wave packet interference; and that should be useful for distributed applications with and without vector clocks and an initial time synchronization service (WhiteRabbit > PTP > NTP Network Time Protocol) https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.4.043041 https://journals.aps.org/prresearch/abstract/10.1103/PhysRev... : > The [quantum time-keeping application of this research] relies on the unique fingerprint that is created by the time-dependent photoionization of these complex wave packets. These fingerprints determine how much time has passed since the wave packet was formed and provide an assurance that the measured time is correct. Unlike any other clock, this quantum watch does not utilize a counter and is fully quantum mechanical in its nature. The quantum watch has the potential to become an invaluable tool in pump-probe spectroscopy due to its simplicity, assurance of accuracy, and ability to provide an absolute timestamp, i.e., there is no need to find time zero. IIUC a Rydberg antenna can read and/or write such noise? "Patterns of Distributed Systems (2022)" https://news.ycombinator.com/item?id=36504073 https://news.ycombinator.com/item?id=36504073